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Title: Constitution of the South Boston Dorcas Total Abstinence Society
Date: 1844
Description: Constitution of Ladies' Abstinence Society. Instituted 1844

Title: American Railroad Journal March 27, 1847
Date: 1847-03-27, 1847-03-27

Title: American Railroad Journal February 1, 1842
Date: 1842-02-01, 1842-02-01

Title: American Railroad Journal March 1, 1841
Date: 1841-03-01
Text: AMERICAN RAILROAD JOURNAL, AND MECHANICS’ MAGAZINE. ‘§§l;e£?" J MARCH 1a 1840- jn placing before our readers Mr. Ellet’s plan for a suspension bridge for the Schuylkill, at Philadelphia, we beg to congratulate them upon the prospect of a reintroduction of this mode of bridge building. We have frequently commented upon the importance of this subject. and it may be remembered, that when intr...
Show moreAMERICAN RAILROAD JOURNAL, AND MECHANICS’ MAGAZINE. ‘§§l;e£?" J MARCH 1a 1840- jn placing before our readers Mr. Ellet’s plan for a suspension bridge for the Schuylkill, at Philadelphia, we beg to congratulate them upon the prospect of a reintroduction of this mode of bridge building. We have frequently commented upon the importance of this subject. and it may be remembered, that when introducing Mr. Ellet’s pamphlet, on Wire Bridges, that we suggested the adoption of this form of structure for the Croton Acqueduct at Harlem river. Mr. Ellet, long since proposed a suspension bridge, but as no deﬁriite plan has yet been agreed upon, we think it not too late to take him up. We repeat what we then said, that afailure of the high bridge in even a small portion would cost more thanacomplete,VVire Bridge which would answer in every particular. In these days of econo- my and retrenchment, it becomes our VVater Commissioners to look well before they leap. SUSPENSION BRIDGES.——-PLAN on THE WIRE SUSPENSION BRIDGE ABOUT TO BE CONSTIIUCTED ACROSS THE SCHUYLKILL, AT PHILA- DELPHIA. By Charles Ellet, .772, Civil Engineer. The wire suspension bridge represented in the annexed engraving, was designed in compliance with an invitation of the Commissioners ofthe city and county of Philadelphia; and is intended to succeed the Fairmount bridge, which Was destroyed by ﬁre in the summer of 1838. The plan was approved by the Board, who have since advertised for proposals for the erection of the work; -and it is understood to be their intention to urge its immediate completion. . A L A Without adverting to the merits of this plan, as a particular application of the principle of suspension; the fact that sucha bridge is aliout to be constructed, cannot but be a matter of interest to the profession, as an aus- picecoi‘ the introduction into»th,is country of an impromnﬁnt which has de- served and acquired the most abunddrp success abroad. . I , 130 Canwnmticatians. Suspension bridges present many claims for public attention, which have been fully recognized wherever they have been fairly submitted to the test of experience. Nearly all the principal rivers of the cultivated portions of Europe ﬂow through densely populated districts, in which the impop. tance of an unembarrassed communication with the opposite shores, has been long appreciated; and bridges were consequently established at an early period, wherever the interest was suﬁicicnt to ustify the expense of their erection. But nevertheless, as soon as one or two suspension bridges had been successfully accomplished, it wasfound that there were numerous places where similar works were greatlyneeded, and where the abilities of the inhabitants had yet proved to be unequal to the charge required for their erection and maintenance, bydthe application of any system of con- struction previously devised, which might thence‘Fot'tli participate in the ad- vantages held out by the new method. In the course of very few years, great numbers were/accordingly erected; and it soon became manifest that the anticipated objections to the recent innovation were either entirely fan- ciful, or such as could be readily removed. Popular opinion had foreseen inconvenience from the supposed instability of the platform ;i but experience taught, that when properly built, the mo- tioniin an arch of 300 feet opening, or more, did not exceed that which has place in ordinary wooden bridges; and theory at the same time demon- strated that the oscillations produced by an equal disturbing force diminish as the length of the span is augrnente.d.i The apprehension of a ‘rupture of the cables, was dissipated before the ‘proofs which were furnished by science and experiment;-—proofs which show that of all the applications of building materials to architectural purposes, none admitted of greater certainty than that of iron, and especial» ' ly of iron wire, to the support of bridges; that the tension to whichthe metal was ‘exposed, is susceptible of the most rigorous ,determination, and its strength, of the_most accurate preparatory trials. At the same time that these positive objections were relieved, the com- parative value of the system was made equally apparent. The unrivalled beauty, and even gracefulness, of those examples which had been con~ structed, gave them a preference for positions where ornament was essen- tial and elegance a merit. Their susceptibility of being applied to rivers. where the width of span must necessarily be very great, rendered them pe- culiarly appropriate for situations in which it was requisite, for the preser- vation of the navigation, or otherobject, to avoid obstructing the water way by the establishment of too many piers in the channel.“ They.pos- sessecl, withall, the merit of durability, to an extent whichwill render‘th‘em monumental; and to these advantages was superadded a claim not unt're- +_* ‘The span of the Freibourg brid e, built by M. Chaley, is 889 English feet and its ﬂoor- in is 167 feet above the surface of the Sarine. Another bridge in Switzerland, b the same 0 car, over the valley of Gottron, has a span of 152 metres (499 fcet,) and is e evated'34'0 feet above_the bottom of the valley. Ships pass under the ﬂooring of the Menai bridgcun- der full sail. ' ' ' T Comma-mbaitians. 151 rpiontly esteemed as still more important: viz. that the first outlay neces- sary for their construction, will generally be less than that for anyother de- scription of bridges. There are exceptions to this assertion, but where they obtain, the stream must be very inconsiderable, and such as will por~ bination of the materials. . With these c.laims—which in fact cover the whole ground, on which a preference could. be founded--—the system of suspension prevailed through- out Europe 5. and was immediately applied to the most important streams, in the heart of populous cities, and on various lines of railroads. -. Arches were commenced and successfully accomplished, from two to three times as wide as had ever, before been attempted; and the practice of constructing bridges of any other description, was nearly superseded by the favor yield- ed to a system which appeared to combine every possible advantage, with a susceptibility for universal application, and which could scarcely be oppo.s~ ed by one solid objection. . . The rivers of the United States, and especially those west of the Alle. ghany, present a broad field for the introduction and development of this improvement. In general, these streams are remarkably wide, and subject to freshets of great height and power; they are navigable for steam boats during a certain portion of the year, and sustain =1 commerce of the high- est value to the country; considerations which may be regarded as so many objections to the obstructing of their channels by piers, independently of the expense which the erection of such works, in these circumstances necessa- rily involves. Besides, the sparseness of’ the population in most of the States, and the deﬁciency of funds incident to that condition of things, ren- ders it important to ﬁx on plans which will at the same time require the smallest annual charge for maintenance, and the smallest capital -for origi- nal construction. l " _ These conditions are best satisﬁed by the pendant principle; and its in- troduction into this country must therefore be regarded as a valuable contri- bution to the means of perfecting our great and numerous lines of inter- communication. - T t p The engraving of the bridge intended to be constructed acrossthe Schuyl- kill offers a very faint idea ofthe appearance presented by such a structure, when tastefully designed and viewed in place. It will, however, serve to convey an impressionof thegeneral appearance of suspension bridges, to those who have not possessed the opportunity of witnessing some of the ﬁne specimens ofthe art which have of late years been erected in Europe. This bridge consists of one principal opening 400 feet wide, and two lat- eral stone arches of 65 feet. Upon the piers which sustain thethrust of these lateral arches are to be erected 4 isolated columns for the“. upport of the wire cables which uphold the platform. There are four of these cables, each of which is about 600 feet in length, from 4 to 5 inches in diameter, and composed of about 900 strands of iron wire. The wire is the 14,, of _mit the adoption of the wooden bridge requiring the simplest possible com- [39 Cu7m2zun~icati072s-. £0 a foot in diameter; and each strand is covered with 21 coat of‘ durable var. nish before it is put in-the cable. , i V The cables pass over the summits of the granite columns, where they bear on a moveable saddle, resting on rollers of cast iron, which are placed between ‘the saddle and the upper surface of the capital. These rollers have aslight play, and the object of introducingthem is to prevent the col- umns from being disturbed by movements ofthe cables, whether caused by the dilatation of the wire consequent on atmospherical changes of temper. ature, or the small oscillations and vibratory movements of the platform. The ends ofthe cables descend through appertnres in the masonry, and are securely anchored in the abutments of the littoral arches; passages are formed for theieasy access ofthe superintendent to these fastenings, in order to admit, if necessary, of the removal ofa cable, or the application of fresh paint or varnish to the iron as often as it may be judged expedient. Thewidth of the ﬂooring of the bridge is 26 feet; of which space 18 feet in the centre, is intended for a carriage way, and 4 feet on each side, next to the parapets, for foot ways. The foot ways are raised 10 inches above the level of the carriage way. The dimensions of the cables are assigned with a view to the support of the bridge when the whole area of the platform is occupied by people; and it is assumed, in the calculation, that the number who can conveniently standupon it is equal to 3500 men of ordinary stature. The weight of this number of people, estimated at 150 pounds per man, is 234 tons. The weight ofthe bridge, or of that portion ofit which is suspended between the columns, is computed at 214 tons; and consequently the whole weight on the cables, where the platform supports a load of this amount, will be 448 tons; from which will result a tension at the points of support--—the sum- mits ofthe columns—of 720 tons. The ultimate tenacity ofthe wire which will be used, may be safely estimated at three ﬁfths of a ton for each strand; so that the aggregate strength of all the wires in the. four cables--which contain 3600 strand——will be2160 tons; or three times the tension to which they will be exposed when the ﬂooring is occupied by 3500 men. The bridge is to be sustained by 4 granite columns standing on bases 9 feet square; which are obviously too light to be depended on for the sup- port of any material part of the tension; and it is consequently essential that the direction of [the cables, on the opposite sides of the columns should be such, that the resultant may fall as nearly as possible in the centre of their bases. By this arrangement the horizontal components of the tension neu- tralize each other, and each column is subjected only to a pressure in the di- ' ‘rection of its axis, of about 225 tons,or half the weight of the bridge and its load. The stability of the columns is consequently greatly increased by the ‘weight which they sustain; and it would be much more difficult to overthrow them when crossed by the cables and receiving the pressure due to the load which‘ they support, than when isolated. , The platform is one foot higher in the centre than at the abutments; and Ctrmmuniaations. 133 it is guarded on the sides by parapets, which fulﬁl the double ofiice of pro- tecting the passengers and reducing the oscillations to which the structure is liable. _ . The preceeding remarks apply to the plan of the bridge as it was pre. sented and approved ; but since its‘ adoption by the commissioners a change ofthe location has caused certain modiﬁcations to be made to adapt it to the new site. i For the Amcrican'Railroad Journal and Mechanics’ Magazine. INTERNAL IMPROVEMENTS on NEW YORK. NO. 4. ‘ . \’Ve have shown in the preceeding numbers that, by lengthening the locks of the Erie canal, and constructing duplicate ones at certain points, its ca- pacity for the transportation of freight will be doubled, and by an improve- ment in its channel, in raising the surface 1 to 112- feet, and adding to the width 16 feet, its capacity will be fully quadruple what it now is, and such proportions obtained in respect to the size of the boats and the canal, as will render the cost of transportation with animal power a minimum. . All this may be accomplished at an expense not exceeding six millions of dollars, or about the one seventh part of the cost of the enlargement on the plan contemplated. The State will save by this plan nearly $30,000,000—— the canal will be abundantly large enough to accommodate any prospec- A tive increase in the trade upon it for years to come, and the great desidera- turn of cheap transportation, eflbctetl to a degree as perfect, when all the attendant circumstances are considered, as can be attained by the proposed enlargement. . - Although the arguments advanced, are believed to be quite sufﬁcient to . justify the conclusions to which we have arrived, we will give some further reasons in conﬁrmation of their correctness. Supposing the Erie canal to be enlarged the whole distance from Albany to Buffalo, it is easy to perceive that a similar improvement of the Oswego canal will speedily follow. The limited extent of the Oswego canal only 38 miles", half of which is natural navigation, and being, as it is, the chan- nel of communication with lake Ontario, its importance is such as leaves no reason to doubt that its enlargerhent will follow that of the Erie canal, as certainly as its construction followed that of the Erie canal in the first instance. l . . 7 _ V The Cayuga and Seneca canal connecting with the Cayuga and Seneca lakes, and communicating with a fertile and populous portion of the State will also present claims for and enlargement which will be irresistable, and hence we may reasonably expect that if the plan of the enlargement is per- severed in, the State in order to perfect the system will be forcedlinto the expenditure of some seven or eight millions more than has been estimated. The advocates of the Erie Canal enlargement, although they must have seen the necessity of adding also to the size of these canals, have been si- lent on the subject. They have advocated the enlargement on the ground 1.3}; Efommurr-icatians. that the large boats would he better adapted to the navigation of the find. son river and the lakes mentioned in the interior of the State, but have been silent as to the whole expense necessary to be incurred in carrying this plan into ~eﬁE‘ect. i As to the other canals to which the enlightened internal improvement policy of the State has given birth,,viz. the Chemung, Crooked Lake, Che- nango, and the two less hopeful ones yet in embryo, the Black river and the Genessee valley, there is no danger of their acquiring an importance sufﬁcient to render their enlargement in the least degree probable. These canals, however, in connection with the two first named, until such time as they shall be enlarged, must labor under the very serious inconvenience of a transhipment of freight to and from the boats of the Erie canal at the sev- eral points of junction, owing to the different dimensions of the boats and character of the navigation upon each. i The delay, expense and embarrassment of this transhipment has not been fully realised. t . It has been shown from published reports, that-* of the 640,000 tons which came to tide water on the Erie canal inthe year 1838, two-thirds was lum~ her or the product of the forest. It is well known that most of this is brought to the Erie canal from the lateral canals ‘and is transported the most of it in boats. Flour, also, and other articles, are furnished in large quantities from the lateral canals, particularly the Oswego and Cayuga and Seneca. v ' 2 The expense of transhipment must of course depend very much upon the nature ofthelading, and will embrace the following items. 1. The interest on the cost, andldepreqiation of the boats duringthe time occupied in making the transfer. 2. Wages of boat hands for the same time. 3. Interest upon the cost, depreciation and feed of horses. M L 4. Dock rents and ﬁxtures, and occasional warehousing expenses. T 5. Such additional hands as may be necessary. V By giving" to these several items their proper value, it will be found, we ‘believe, that the average cost of transhipment, independent of the embar- rassment consequent upon the delay, and the injury upon the articles tran~ shiped, will be not much less than ﬁfty cents per ton, or equal to’ the pre- sent average cost oftransportation of down freight, independent of tollson ﬁfty miles oflthe canal. _ T . Supposing, therefore, as is asserted, that the saving in the cost of trans- portation on _the enlarged canal will be 50 per cent of , the present rates, freight from the branch canals must be.’ carried 100 miles on the Erie ca- nal to make the expense what it ‘now is. Putting the saving at 25 per cent- instead of 50, which is undoubtedly nearer the truth, and the distance at which the expense will be the same as at present, is 200 miles. That is’, if the ‘distance at which freight from the lateral canals is carried in the Erie .eanal,is‘*le‘ss than 200 miles, the total cost of transportation "will be greater Communicatisom. ‘ 135 than it now is. This certainly does not show any very great advantage to be derived by the sections of country in the vicinity of the branch canals from the enlargement, unless the circumstance of paying as /tigh or higher than they now do for transportation, and bearing, at the same’ time, their portion ofthe burden of the debt to be contracted, can be esteemed an ad vantage. Again, those who are conversant with the mode in which the transpor- tation is conducted on the Erie canal, are aware thatthe business is almost wholly in the hands of companies acting in concert and wielding an im- mense capital, and hence are able to defy all ordinary competition, monopo- lising the business, and becoming carriers at their own prices. The power and extent of this combination, although, its inﬂuence was then but partially developed, were manifested when in 1833 the Canal Board reduced the tolls to near the constitutional limit, with a View of bringing in the trade of the country west of Buffalo. ’l1’1iSt\(-’a(l of produc- ing the effect anticipated, the forwarding companies immediately raised their charges, thus converting a measure of great public beneﬁt into a source of private emolument. , If the Erie canal is improved so as to admit of any material reduction in the cost of transportation, what guarantee have the public that the same scenes will not be re-enacted, and that instead of deriving any beneﬁt them- selves from so great an expenditure they are not putting money into ‘the coffers of a monopoly which has already rendered itself odious by its un- reasonable exactions? Certain it is, that however great is the evil of this monopoly at the present time, it will be much augmented should the project of the enlargement be accomplished. This follows from the fact of the business being conducted on a larger scale, the boats being larger and more expensive to build and to navigate will prevent many from engagingin the business of transportation, and drive therefrom also many who are now engaged, but whose capital and means -although adequate to prevent ex- igencies are too limited for the purchase and navigation of boats upon the large canal. - There are still other reasons why the cost of transportation will not pro- bably be reduced to the degree anticipated. The line of railway alluded to in a previous number, extending from Albany to Btuifalo, will soon be completed. , The restrictions imposed by the. State upon the railway, as it regards the conveyance of freight, opposed, as it is, to the enlightened prin- ciples of political economy, and the true interests of the people of the State, will ere long be removed, and when so removed, the railway will carry a n very large proportion of the merchandize, which -now pays, for both tolls and transportation, more than double the charges upon other de- scriptions of freight. This change will not only make considerable. inroads upon the tolls from the canal, but the forwarders’ loosing, as they will, their very great proﬁts ‘on merchandize will be compelled to charge higher ‘on other freight. ‘This, although it may not cause any in- 135 ‘Communications. crease in charges over present prices, will prevent their being reduced 3, low as_ they otherwise would be. That the railway will carry merchandize to a very considerable extent, when the restrictions alluded to are removed, is obvious from the experi- ence on the lakes, where the steamboats take most ofthe freightof this de. scription at much higher rates than sail vessels, principally on account of the ‘ saving in time by that mode ofconveyance. Rapiclity and certainty of conveyanceiare. very importantto the merchant located in the distant interior. It gives him a more speetly return on capi. tal invested, and with the convenience which a winter conveyance upon a railway will afford, he will not be obliged to purchase so largely when procuring his fall supplies, and thus derive a double advantage in the con- stant receipt of fresh supplies, according as his necessities may require, and in the less amount of capital needful for the transaction of his business. That the transportation of mcrcliandize upon the railway will take place, to a very great extent is obvious for another reason. If but a single mer- chant in a village or city in the interior should obtain his supplies by the more speedy conveyance of the railway, others will be compelled to do the same, and that such will he the natural course which business will take, ap- pears to us to be too obvious to need further comment. As to the effect of a reduction in the charges of transportation uponthe canal in drawing to it a greater amount of business by ])L1Sl]lt'lg further to the south and west the dividing line which separates the portions of the valley of the St. Lawrence and upper Mississippi doing business respective- ly with New York and the cities south, we cannot but believe the anticipa- tions of the friends of the enlargement have been too sanguine. The tide of emigration to the States and Te‘rt'it0I'ir.'S west, is Ytrt strong and will un- doubtedly so continue for many years to come, the consequence of which is a consumption within their own borders, of their surplus products, leav- ing comparatively little for the Atlantic marts. That the inﬂuence of a reduction of tolls in inviting business to the ca- nal from the sections of country mentioned, must for some time be limited, appears probable from the fact that the business of" the canal thus hit has been mainly from within the limits of’ N. York, notwithstanding in the last six or seven years there has been a general reduction of 25 per ct. upon the tolls and a further reduction offull 30 per ct, arrising out of the extraordi- nary advance in prices, which for the last ﬁve years has taken place under the benign influence of the credit system. The country having began to realize the bitter fruits of making that which is a. mere (H.-irlcitce of debt a sla,nrZm'r1 of value, or in other words, of giving to paper which possesses no intrinsic value, the properties of coin, there is every reason to believe that prices will rec«:»cle until they..shall reach a’ point at which they can be permanently maintained. The tolls of the canal being based not upon the value but upon the weight or dimensions of the several rrommorlitins, this reduction in prices is practically equivalent to an inc;-arise in tolls. C6m'mnnic'atio‘m. I 37 The business of the canal must, to a considerable extent, experience the ...jurious effect of this change in prices, or relative increase" in tolls, the remedy, supposing it expedient to apply any, which is doubtful,being be- yond the reach ofthe. State authorities, since the tolls are now down to the . limit ﬁxed by the constitution. ‘ There is another view of the subject ofthe probable effect of the enlarger -ment in reducing the charges for transportation which merits the most se -rious attention. In ‘the report -of the comptroller for the year 1838, -from which we quote, not having" the ‘last report at hand to refer to, the nett revenue of the the State canals is thus given. Surplus ofthe revenues ofthe canals from tolls over and above the cost oftheir maintenance, $84_1,88s'09 Ifthe int_erest paidlfor the year on thedebt ofthe lateral canals which are ﬁmls/Le/Z, be deducted, 170,000,00 It leaves a surplus of The revenue from the Erie and Champlain canals, being the only canals. which more than pay expenses, has not varied much for the last sevenyears. During the whole of this time it has ranged between $1,300,000 and $1,400,000. This being the fact, there is no good reason to believe that the increase will be very rapid forseveral years to come. a If it remains the same, the onlyavailable means of the State, derived from the canals, for paying off’ the clebt of the enlargement, is the surplus above stated of $671,- 888.09. This it must be remarked, is the surplus after paying interest, without reducing the principal of the debt ofthe lateral canals which are __/in/islted. It does not therefore include the two last of the pamper progeny -of the State, viz., the Black River and the Genessee Valley. ‘ The interest -on these being deducted, amounting to $600,000, it being doubtfulwhether they will ever pay the cost ‘of maintenance, and there remains but a precious small sum for defraying the interest onthe cost of the enlargement, amount-. ing, at 6 per cent., to $2,400,000. per annum.‘ That the revenue of the Erie canal will continue to increase, we ﬁrmly believe—but the expensesﬂrlso will increase ;’ and it should be bornein‘ mind that the most liberahestima-te of ‘the revenue for many years, will not be suﬂicient to keepdoxvn the interest, if the plan of the ‘enlargement is persevered in,and a resort to taxation will become necessary topreserve the faith of the State, and obtain means for defraying‘the« current».ex'p'enses of the government. if the enlargement of the Erie canal is accomplished on the sdalelproposedlits‘probablecost for reasons given in ‘our first number will 'am"oun"t to $40,000,000‘ Debt of the lateral ‘canals in ’o"pe'ration, about i2}h00.000 Costg’oi' the ‘étenessee Vaallefy canal. 6,000,000" .Bila‘c‘l:‘ rivet’ 0 -l=.00'0}09W’ 18 138 Communications. g Expense to beincurred in enlarging the Cayuga and Seneca, and Oswego canals, say 7,000,009 “ rebuilding locks on Chemung canal of stone, they being now of wood and almost useless, 700,000 " rebuilding also the locks on Chenango canal which are of stone and wood, 1,300,000 « ’lt6l.,500,000 The State of New York, without entering into any new projects, is al- ready in for about $60,000,000 on account of her canals alone without even areasonable prospect of being able without resort to taxation,‘to pay the intereston that amount. Is it not time to pause in this career of extrav- agance. Of all the visionary projects into which the State has been drawn by the inﬂuence of unwise counsels, the enlargement of the Eric 60» I nal is the most visionary, and the sooner she malccs haste to -retrace her steps the better. A Furxron. t For the American Railroad Journal and Mechanics’ Magazine. ATMOSPHERIC RESISTANCE TO LOCOMOTION ON RAILROADS— -DR. LAR.D- , NEn’s EXPERIMENTS, m*c.. BY WM. M’c1.Er.LANn onsmuan, oivrr. ENGINEER. A t I I avail myself of a favorable occasion to notice. some alledged discoverie in respect to the quantity of resistance the atmosphere makes to the pro- gress ofa train of cars when tracked by‘ locomotive engines. M The stric- tures upon this subject published in the third number of your Journal, abundantly evince the character of Dr. Lardner’s claims, and his total failv tire to establish any thing, either original or secondary. I, howeverpfeel myself called upon to give some further attention to the subject, in my own behalf; inasmuch as Ihad long since investigated its effects, and published a formula expressing them, in July last year, as part ol'a “new expression of the powers, velocity, etc_., of locomotive*engines.” I intend, however, while noticing Dr. Lardnerls pretensions, to restrict myself chieﬂy to the more Eulldevelopment of the rationale of atmospheric resistance, than Ithen had occasion to do—,-._—a practical ‘indication of its value being all I, at that ‘ time, aimed to effect. It. may be remarked that the views in question first enlightened our horizon the present month, and were published in England, in October last. This statement would be abundantly sufﬁcient in pointoft priority, even assuming them to be true or tenable; but I may here be al- lowed to repeat that (as stated in myﬂpaper of July) my expression was in» , Vesllgated. inextemo, “ on perusal of Chev.’ de ,Pambour’s work”—,—which, was in the fall of the year of its publication. So that the effect of the at- mosphere upon locomotion on railroads, had been established with pyrecigionl in thi_s.country, some three years since and more ; , and published sorrta.ei,ght., months before we were informed (and it may be very trueindeed) that “ no’ Com mtlnica*tioy1;s, 139 details exist, nor have any experiments ever been made, by which the resist- ance (to wit, such as Dr. Lardner has discovered) of the airto a train of rail- way carriages could be obtained by any calculation whatever; nor was the amount of such resistance ever suspected, even by the persons who have ven- tured to utter such statements, as have (has (2) here (to wit, by himself) been - proved to exist.” _I for one (and most engineers will join me) must confess that 1 never did entertainasuspicion of such resistance, etc., as is set forth in this famous course of experiments. i - I may perhaps be indulged in a reflection. It is not an unusual’ occur-V rence for unprofessional men to fall into egregious errors, when they pass from the popular and merely descriptive knowledge of a subject, to the de- velopment and application of complicate laws and principles topractical pur-i poses-—-which is properly the province of the engineer. This I take to be the case in the present instance. As a popularlecturer upon the steam engine, Dr. L. has justly a high repute—that his fame rests here alone has been illustrated in more than one instance. Lethis admirers recur to his it extremely absurd estimates of the capabilities of the superb steam palaces ifeptive...pressute,gof stearn exerted, when t now ‘ﬂying between the shores of the ancient and modern hemispheres- secure and uniform, maugre all presages——as if plying between the banks which sustain two opposite marts on thepi-Iudson. i _ In illustrating the rationale of atmospheric action upon a train of rail- way carriages,-«it will be best, in the ﬁrst instance, to pre-establish, by spe- «cific statements, an idea of the proportion of motive power actually annulled ‘by such action, when performing regularly the (l?l«l_’l/ required in. pra.ctice——v-i * .«ot"her'*trials, upon trgiins allowed to generate their own speed, can in few, if any instances, be of service in researches made with the view of determining the actual amount of resistance, thoughthey may servepfor illustrating a ‘point; and such consequently do not present the data required in forming «conclusive opinions. This distinction will be carefully observed; for "er-’ ratic opinions upon this subject, are very generally, if not exclusively, to be_ referred to indiscriminate reliance upon this class of trials as practical results. ,(Nole.) f , _ W , , L s I have shown (R. Rijlournal, vol. 9, No. 2.) that, upon several lines of railroad of the same width of track, even with engines of. very dissimilar constructions, the atmospheric resistance to the progress of the engine and. train, was, general, very nearly expressed by the forrnula '4 .93, the ve. hairy" of the motion being 2; miles per hour. At 30 mlles per hour. (ave- Iocity exceeding the average rate of motion upon any railroad extant) «the resistance is then 3601133. ‘Now, the maximum .eﬂ"ectiv,e power or force of? steam, of the most puissant engines of ‘the Liverpool railroad, ‘IS 2112 1'bs;, when ._wo'rkingi with their usual pressure in the boiler-,-—to\v1t,.7llll_l>s*-. The~ p,rqpprtion.of,po\ver annulled then, will not exceed of the,mt1X1m|im 99- ‘ ' he velocity is greater than the a.c~. t1(,‘q*)\lWz'g,t.gy»,gj:,trq1,g1;71,1iqzg'_upQfL any railway in this or the other hemisphere», 140 G.ommnnication's: At 20 mm PM how.’ its value is 1.60 lbs, o1-11,3; the eﬂectig-e1:ot'ceofsteam, as ghis is,a_b()ui.' equal to the friction of‘ the engine, unloaded, It Will furnish ,1 Very good notionpofthe amount of opposition experienced, as well as of Its relative consequence as part ofthe total tractrve force the engine is capable of exerting. This velocity is the actual rate of ‘t/Le passengertratns upon ma Liveypqol, and upo_n some of the best roads in this country. .FTeZg‘ht tmtns usually travel at more moderate rates-——the average rate being l2'5~ miles per hour. The resistance for these is then 62 lbs. or 51.; part of the effective force the engineis capable_of’exerting. It 1s certain therefore, that, allowing the obstructionto be considerable, and always large enough: to form a necessary element in reckoning the total resisting forces to been- countered, those other elements ofthe total resisting force must still always greatly predominate over that of the air—--in the practical operation of". rail.» roads. , ‘ ’ ‘ For further illustration in this respect, the following table is submitted‘, it iscomputed according to formula previously exhibited’, viz: '4 o’. - - ' ' loss 1 in 2t1.2 . Velocu of the Engine 5. Acl_ualres1stanceoftl1e 10,‘Proportion the H in mi as per hour. 10. air upon the train at 40. or effect bears to } “ 15. those velocities in lbs. 90. the maximum “ 2 .5 20. nvoirdupoise. 160. Dpwer of the en: 1 “ 13-2. 25. 250. game. It " 8.45 30_ o 350, 1 “ 3.37. 35. 490; 1 4.31 The amount of ‘atmospheric resistance does not depend, in any sensible degree, upon the lengt/tior volume of the train. A The Atlas, the engine instanced above, with a train of 40 cars, does not show any’ greater proportionate resistance, at the same speed, than with a.~ train of but 12 cars, In the ﬁrst instance its train was about 475; feet long, in the second only 160. ‘feet or but one-third the volume of the former. The same conclusion follows from each approved result of that course of experiments; ‘wherein it has already been stated, the quantity of’ resistance i-s generally expressed by the formula of '42:3; that is, to use ordinary language, the resistance is alwayslconstant with the same velocity I have fouvrzdlveryt precisely the same resu:lt'upon other ioads wherever an oppor- tunity has offered to test it by well conducted experiment, even with trains of much greater length than the longest of those speciﬁed. Dr. Lardner, therefore, asserts the precise contrary of the results of extended experience upon engines, rvkile doing their usual requirements, when he says‘ that the résistancefrom the air is measnreol only by the volume of thevtrain. Expe- rience drawn from the objects themselves being repugnant to this opinion, -I beg leave to inquire if it has any indirect support from analogy. Now nothing has been more fully settled by a series of excellent experiments, thanithis. ‘Takea body constituted of two cones placed base to base '(the. height of each=d~iam. of base.) and impel it through a ﬂuid in the direction of -its=axis, and a certain force will be’ required: but on interpolating a short cylinder between the cones, the force required, to move the‘ lengthened body with‘ the ‘sameavelocitq-y, will not be nearly so igreat‘—-if, the ﬂuid bewmerf Clarnmunicartiorts. 141 for instance, the reduction of resistance will be in the ratio 380 to 1000, Again, a blunt cylinder, impelled with any velocity, through the air, re- -quires less force than a cone or hemisphere with the ﬂat side presented- «the reduction being expressed in the relation of the Nos. 288 to 291 and ‘288. Passing to instances upon :1 practical scale, observation instructs us, -‘that upon canals, boats of length require less force to track them, than short boats of equal transverse section : another instancein point is that the speed i of steamérs has, in many instances, been increased without changing their machinery——simply by sawing and interpolating. a-midships—"——that is, the resistance has been reduced by the addition in length. Could the precise section of frontage of a train be obtained with certainty, by direct means, there is no reason to doubt but that a rigid plane surface of ‘equal extent, tracked by an engine, would require much more force to impel, at equal .-speed, than the train of which it is the section, would. The rationale of’ this is perfectly understood—with the cylinder, long hulks, &c., the ﬂuid does more readily and perfectly follow and replace the vacuity left behind tthem as they advance, than with the other objects of equal section—-and a_l~ ‘though a certain increase'ofl'res'istance in the article offriction, does attend «-increment of length,-it has evidently little isignificancein comparison with- the force required to overcome the mere unbalanced pressure of ﬂuid al- ways superadded to its resistance proper, in proportion as the ﬁgure favors the formation of a void in rear of ‘the object.’ Analogies strictly in point, do not, then, give any support tosuch views as have been advanced by Dr. Lardner; but quite the reverse, they bid us rather to apprehend that the quantity of atmospheric resistance is at least as great, when an engine and tender move off without any useful load, as when it has a train in convoy. The general expression of the resistance which has been established irnay be translated into language in these. terms, viz. y The resistance of the air upon strains tracked by locomotive engines is as if made upon an invariable section of frontage, and varies in amount only with the velocity of motion -—upon any given line of road. These results. which have been deduced from regular performances, are besides perfectly agreeable to analogy; and'it is also evident that none other than these are consistent with the established laws of pneumatics. But that no part even of the resistance (in the way of increase at least) has any dependence upon the volume of the train, maybe more clearly perceived on evolving the re- sisting section implied by the-’---formula and bringing it into contrast with measures tahenupon the engines themselves. For this purpose, put S for the unknown section of frontage implied by the formula, agreeably to the principle bf pneumatics, and p for the resistance of a square foot of surface, iatany observed velocity represented by 1:’ miles per hour. We have then . . 1:3 forthe total resistance of the air upon a train ]JS,7'§ lbs., or more exactly » i. 2 §ti‘u,,b,y_(hg., law of B01-da, ,p(_s 2 3,; lbs. atanytime when the engine 142 Cornmunicatiotnz is running with a speed of 1: miles per hour. -Now if the frontagavalone determines the a'asz'stctnce, this last expressionwillebe equal to -4'v3 thevalue deduced from the observed perforrnance of enginves—-that is, we will- have’ J. 2-2 92 _l 4 P (S 2) 1-J.-,3='4u9 and ultimately S==( 752 T1-T P for the area of front .age which must hcwe been present, according to established principles in the series of performances. And this deduced area and that made up from meas- .ures upon the engines, cannot be allowed to differ sensibly from each other, .on our hypothesis. Now at ‘.20 miles per hour the force upon a square- . - . 400 Tl}. foot of surface IS 1.968 lbs., and consequently S==('4 -1-A33-8 =54i6 fr: expresses accurately the a.gg'rega,te frontage presented by every member of the train reduced to plane surface. Again, it is certain that, l00kingto= facts, there is an unbroken frontage (measuring usually about 6><9'=o4; sq. ft.) included between the sides of the tender or cars one way, and be-— tween the rooﬁng of the tender and base of the furnace, the other, super--e .adding for extra effect upon the small members, the area by direct measures. gproves to be nearly, if not exactly, identical with our first result as evolved from the formula -479. Now if this-formula depended in any sensible de- gree upon theivolume of the train, the near approach of the two results" would have been impossible. On the contrary, in that case, there must‘ have been an excess against the direct 7nea,su7'os--whicli excess. if the nerv- ‘fangled views had any basis to support them, must have been indeﬁnitely great. The facts, as seen, are diametrically the reverse-—for the excess is decidedly in favor of the direct measures, but so slightly as to. give assu-. rance that it can never, alter accounting in» the result all minutia, bemade. to exceed the other by an hundredth part of the total section. ‘ It is plain then, that in practice the resistance, if any thing, is rather less: than the actual frontage would give; but also that the difference is inappro- ciable. _ We are authorised, therefore, to assert that the atmospheric resist»- ance is not only as made upon an tntrawittble section of frontage, but‘ that it depends, exclusioely, upon that section, for its amount. Dr. Lard: ner’s opinions have consequently no foundation in fact and he is welcome to all the credit of their discovery.‘ .Alba,ny, Febrztamg/, 1840. iNo'rE.—The resistance of the air can only be truly deduced from trials‘ -similar to the usual performances of engines-—-there must be uvtiform velo-— city, etc. And it cannot be. obtained during such trials if any other element limiting the speed or power, remains undetermined. This was the case until the law of vaporization, as dependent upon vel‘ncity,ha,dZ been established. Havingdone this, the amount of atmospheric‘ re~ sistance was deduced as represented in the paper containing my new expression of the powers, vzelooities, etc. De Pambour in his i wvork made no attempt to determine. *'either of these‘ elements, however Editorial N otices. 1343 his :measures of’ the {friction of engines and of carriages exclude the- atmospheric inﬂuence enti:ne§ly-—mostof, his trials with engines being made without velocity, and the others at so slow a rate ‘of motion, that its inﬁu: ence was insensihle. By excluding the leading car, he also freed the fric- tion of carriages from its inﬂuence. The value of this last, with the cars- there used, is accuratel-y .8 lbs. per ton, or 3%,. of the gross weight. Hav. ing instituted frequent comparisons of computed, with the running rates, upon several roads, I ﬁnd no reason to disparage that result, in any degree, at least with similar cars. Let it however be observed that light cars have less frictionper ton than laden cars. ‘The rationale of this is in the com- pound nature of friction—-in the former the resistance is made chieﬂy at thefperiphery, where the wheel bears upon the rail——in.- the other, at the ax.le—this last, incars -of the usual dimensions, greatly predominating. This may be mentioned -among the anomalies of de Pambour’s course. SAMUEL seams’ COMBINED RIFLE AND snow GUN. We have had presented to our notice the above named ingeniously con- trived improvement in ﬁrearms. It possesses the grand requisite of all useful improvements in such things—perl'ect simplicity. The piece when used as a riﬂe, resembles ordinaryarms of that descrip- tion, and may be loaded as usual, or at the breech by a metallic Cartridge. Arsmall piece is unscrewed at the muzzle which loosens the inner or riﬂe barrel. This is kept in its place by means of an enlargement at the breech in that portion of the barrel in which the metallic cartridge is ﬁtted. The space thus left when the inner barrel is removed, leaves room for at larger metallic cartridge for the shot gun, which may likewise be loaded in both ways. The rifle sight turns on a pivot,‘ and may be putout of the way when the smooth bore is used. The perfect adaptation of all the parts, renders the united barrels quite as ﬁrm as if in one entire ’piece—- and as a riﬂe it is not heavier—-or as ‘a shot gun, lighter than common arms ofthose kinds. We consider it as completely supplying the place of two distinct pieces, -and combining economy of space and and money. For travellers such a gun would prove invaluable——¥ while-the hunteris thus enabled to command game'of' all descriptions by a single gun. The change may be made in halfa minute,’ from a rifleto a fowlingpiece. We understand that a small’ portion of the right is offered for sale, and we conceive it to be a ﬁne invcstmcnt—-being free from the common objec- tion to improvements in ﬁre arms—complication of parts. We are indebted to Mr." Roeblingl for a communication on the “Theory of the Cranlc,” which camehowever, too late for this number, Itwrll ap- pear in the-next number. Baxmnrs or R.ifr.;i1oAns.~lV-e “copy the following statement'of the performance ofiia-'lo‘comot1v.e ,Stea‘m ‘engine “on a Pennsylvania railroad. Facts like these 8l‘e,'CQ,~l’:'V4ill’~l~Ci’t‘!gi" proofs of tlwrsllperrorlty of railroads over 144: Great performance inf" w Locomotive. canals. To this statement we annex some remarks from the Journal of Gornmeree, elicited by certain articles whlch have recently appeared in the RailroadiJou‘rnal,on the enlargernent of the Erie canal. We profess not to be fully acquainted with this subject, but ifthe large sum of money rte.‘ cessary to complete this enlargement can be turned to the construction of railroads, we are of opinion a much greater good Will be accompllshed. , Ed. N. Y. Times. UNEXAMPLED PERFORMANC1-ZITN TI-[IS COUNTRY on EUROPE.-The engine “ Gowan & Marx,” built by Messrs. Eastwick &. Harrison, for-the 0 Philadelphia and Reading railroad company, weighing eleven tons, drew Peters’ Island, one hundred and one loaded cars. Gross weight of train, 423 tons of 2240 lbs. Nett t; V M H . as . Running time, 5 hours, 23 rninutes—distance 547}; miles, being atan aver- age speed ofabout 10 miles per hour. _ The coal consumed by the engine in drawing this load was 5600 lbs. or rather less than two and a half tons. Thequantity of oil consumed by the \vhole train of cars was 5} quarts, being about halfa gill for each car. The freight was as follows: esterday, over the railway from Reading to the Columbia railroad bridge, 2002 barrels of flour, weighing 1903‘, tons 459 kegs of nails, 22 “ .52 barrels of whiskey, 1 ii! “ 20 hogsheads of corn meal, 13% “ 5 “ whiskey, 3-,} " 7 “ linseed oil, a ,7 “ Lot of band i1'on,\etc., t 19% “ Total nett freight, 268-} “ Philarlelphia Gazette. The following is a statement of the receipt and expense of transporting 423 tons of2240 lbs., over the Philadelphia and Reading railway. The :nett load of 2000 lbs. to the ton. was 307 tons or 101 cars. The freight received by, bills ofparcels was $835 19 for the down trip-rv -or $2 78 per ton of 2000 lbs. carried 54% miles in ﬁve hours and twenty-" ' three minutes. The daily expense of running the locomotive to carry a train one trip, is stated at $16 67 4 ‘To this add wear and ‘tear of 101 cars, at the‘ very liberal allow- 'ance-of 30 cents each per diem, (this rate will renew them every three years,) , 30 30 Addifour handsiat the brakes, 4 Five and a half quarts of oil. - - - A 2 $52 97 The above does not include the incidental expensesiofwa<rehouse and nn-' loading. On the supposition thettthe cars returnempty, it will cost. iil5.1i05 94--—v.it will_ cost at this rate 35 cents to transport oneton of coal, in a train 330 tons, 54; miles, between 6 and 7 mills per ten per m?ilet»¥ Corr_zmunica,tz'zms.w 145 The company calculate to pass daily 2250 tons of coal in ﬁfteen trains ‘with half the above load. This will give them a gross income at $2 per ton on only 708,770 tons, per 315 days, of'$1,4’l7,540. , - i . The facilities of this road, from its favorable grades,to transport coal, far. cxceedsithe Schuylkill canal along side of which it is located. The capacity of the canal is limited to the number -of llockages, during the seasonof transportation. This period will not usually, on an average, (ex- cluding Sundays, left out on the railroad estimate) exceed ‘.200 days,‘ If. a loclcage is allowed every ten minutes, day and night, for thewhole season, with the supposition that each boat carries to tide water, on an average, from the mines, 30 tons of coal,we have 744,000 tons, the capacity of the canals. i As regards the railway, a train with 200 tons could pass every half hour, say for 315 days, equal to 2,994,000 tons. On a well regulated railway, -there would be no difliculty in st-artinga train every 15 minutes--a rail- :I'Oﬂd with a double track, is nearly equal to travelling in a circle.- .A POPULAR‘ EXPGSITION or THE 11~ioorznEo'rNEss on THE TARIFFS or TQLL IN USE ON THE PUBLIC IMPROVEMENTS or THE UNITED STATES. lav CHARLES ELLET, JR., CIVIL ENGINEER. “ SECTION 4.-—On the most jmlicious aha/rge on articles of Ir-envy bu-rrlen -and small value. '12. Iconceive that it is essential to the fulﬁlment of the condition, that the tax levied on the trade of the line shall be reconcilable with principles of equity, that the charge at each point shall beproportional to the ability ‘ «of the ‘article to sustain. And, it fortunately happens, that when the‘ charges are regulated ' in the mode that will produce the maximum revenue, this -condition‘ will be fully satisﬁed. , ' , We are to understand by the ability of a commodity to sustain a charge -for carriage, the difference between the cost of production and the market value of the object. ‘ If the article be worth $10 in market, and it cost $56 tolproduce and prepare it for market, it will sustain any charge for trans portation, including both freight and toll, not exceeding $4. But its ability ‘to sustain a charge foo‘ toll only, depends on the position in which it reaches the line ofthe improvement. For, after deducting the cost of production from the market value, the residue may go to bear the whole cost of car- riage; but we must still deduct from this residue the charge for freight, to obtain the sum which it will bear to be charged for toll. o . A If, for example, the above article reach the line atone hundred miles from the mart, and the freight be one cent per ton per mile, the charge for freight will be $1,, and this residue will be $53. If it reachthe line at two hundred miles, the charge for r"reigh't will be $2, and this residue will be $52.. If it come on the work at three hundred miles, the charge will be $3; and. the residue will be $1 ; and if it reaches itat four hundred miles, the freight will be $4, and theresidue will be nothing. I say, therefore, that "to make the tax for toll proportional to thepability of the commodity, the, charge levied by the State for its passage along 100 miles shioulcl be proportional to $3, 200 mile‘s','sh,ould“be' proportional to $2, 300 miles should be proportional to $1, and along. four hundred milges it should be allowed to pass‘ free. From which it appears, that the greater rim rlistauce. the co_mmo’rIi2‘@/’ is cmwler/. 146 Communications. the less should be the toll levied open it. In short, I propose that'- the tax should be proportional to the abillty of thetrade to sustain the charge; and’ by such a ta'riﬂ","to supersede those now in use-—-by which the tax is ina creased in proportion as the ability of the trade to bear the tax is dimin- ished. ’ ‘ ' 13. Now, it may be demonstrated, that when the toll is assessedton this rinciple, both the tonnage and the revenue. will-. be greater than if the most» proﬁtable uniform charge per mile that it Is possible to levy were'adopted,, Butthe methorl of determining this most productive charge, cannot be conveniently pointed out, with a demonstration of its correctness, in a mere’ e popular discussion.- I have, however, elsewhere considered the subject in . some detail, and have shown that the toll on.th1sd1v1s1on of the trade which. will yield the greatest possible revenue, is about tlrree-eighths of the charge which would exclude the article from market ;: or three-eighths the limit oi? the tax which it would bear. ‘ In the above example, therefore, the charge at A 100 miles, should be three-eighths of $3‘, or $1 1-2.} 200 miles, should be three-eighths of $2,. or 75 300 miles, should be three-eighths of,$1,.orV 371;- 400 miles, ‘ 0 00 y The diﬂ“erence between these sums and those above given constitutes the proﬁts of the proprietors. ‘ It cannot be owected to this -scale of charges, that it deprives the citizen on the line, near the mart, of any of the advantages of his position. The -work, on the contrary, furnishes him with the means of transporting. the products of his estate to a market for one-fourth or one-ﬁfth the sum he was» compelled to expend before its construction. This is a positive advantage for which he is indebted to the commonwealth; and he has no right tocom-— plain, if the same commonwealth extend, the beneﬁts of the enterprseto more distant citizens. Theavowed. object of the improvement is to liring to market productions which could not otherwise reach it, and, generally,. to reduce the tax on transportation. And ifthe objection, that the mode of charginghere recommended may seem to disturb the relative advantages ofposition of the near and distant denizen, be a valid one, it is a. fortz'ari_9z conclusive argument against all improvement. A consequence of the con- struction of any canal or railroad, isto increase the value of estates to which it affords new facilities, and of course disturb the relation between the ad- vantages possessed by such property and other estates in the coinmonwealith, on which it has no eﬁ"ect. , , _ But such an objection, even if a legitimate one, cannot be applied to» the‘ scale here advised. It is not proposed to tax the distant man less for the.- transportation of his effects than the nearer one; on the contrary, heist charged more." The method merely proposes to make that portion of the tax which is to be considered as the proﬁt ofthe State——-that portion which is levied for reven ue——-proportional to the ability of the trade to pay it. And this is justice. ' i ' ' ‘In the example given in art. 12, as weyhaveseen above. the toll _ - For loorniles would be 81 12} 200 W“ “ 75 300' "~ “ 37; i . V 400 t or u on But the whole charge, or freight and toll together For 100 ‘la: would be $2 12 ml‘ ll 2 soot-“ ‘ “ - am ‘ l . - : H ‘ 2 N 4 00 ~91’, actually tncrcaqtng in proportion to th¢d1'st‘ancc. ‘and at the rate of six ands quarter a mtllsper ton peiﬁmtle. . ’ ' ‘ . Ci-om7munic cttioh. . 147 if. If, ‘HOW. We represent by a proper scale, as in Pig. 2, the area of the «country which, with the data of this example, would furnish the tonnage, in ‘the h pothesis of. an uniform charge of one cent for freight and one cent for tol , we shall have, as before stated, a triangular ﬁgure NPN, with a base, NN.*of eighty miles, and height, MP, of two hundred miles. But if the charges were adjusted with aview to theobtaining of the max- .‘imum« revenue, the triangle would have a base, mt, of fifty miles, and a height, MR, of four hundred miles. In the one case the area of the coun- try would be represented by the triangle NPN, and in the other by the tri- cangle 7iRn. ‘ y 15. But, instead of~-aiming to obtain the maximum revenue on all the trade which would reach the improvement from R to M, we ‘may, by the "system whicheit is intended to recommend, adopt in both instances an uni- ‘form chargefor toll, as one cent perton per mile, from M to M’—-the point which corresponds with the intersection rt’ of the sides of the superior and inferior triangles-—and confine the arrangement made with a view tothe maximum revenue, to that portion ofthe country situated between M‘ and R. The consequence of this arrangement would be to obtain the same ton- nage and revenue from the country traversed by the portion MM’ of the “line, in both cases, since the tariff‘ would in that distance be common; and “at the same time to increase the area ofthe country trading on the improve- ment, a quantity equal to whatever would be due to this additional trade and the charge upon it, determined in accordance with the principles here laid down. , . 16. It will be perceived that the increase of tonnage and revenue which, ' in the preceding article, is shown to have place, will be obtained without any increase of toll on any part whatever of the trade. Wehave only to ‘take the present tariff of New York or Pennsylvania, or any other state or company, and obtain these results by/(I, reduction of the charges. For, at the point P, which is supposed to betwo hundred miles from M, we have seen that a toll of one cent per ton per mile would entirely exclude the trade. r But if instead of a charge of one cent per ton per mile, at that point, or $2 for the entire toll from P toll/I, the article were taxed hutseven- -ty-ﬁve cents per ton, as is stated (in article 13) to be the proper toll under the circumstances, there would remain out ofthetwo 5152, which is the limit of the charge for toll it would bear at that position, a balance of $1 25 to pay the expense of its transportation. from ya to P—-—a distance of twelve and a half miles on each side of the line. So that, by simply reducing the charge resulting from a tariff proportioned to the distance, we shall here obtain, instead of nothing, a revenue due to the tonnage that would be fur- nished by a districtpp, twenty-ﬁve miles in breadth, at a charge of seventy- ﬁve cents per ton. , ‘ - r Itis true that a much more important increase of revenue might be ex- perienced by a modiﬁcation of the uniform charge supposed to be levied from M to M’, and a reduction from the new tariff beyond M’. For, even where we adoptthe principle of fixing on the determinate toll per ton per .mile for a certain distance, we should hear in mind that there is a certain uniform charge which will yield a higher result than any other. But, Without any reference to this, or any of the other advantages which would be derived from a thorough, and strict regard to the laws of trade in the es- tablishment of the ta riff, I have only soughtto render clear the fact, that by simple reductions of the charges on (L portion of the trade on all our public 'wa.rks, the revenue and tonnage ma_,_7/ be simrtltcmcausly increased, a/ztrl the ma.‘ on the public may be rendered more equitable. — ' r I7.~The preceding coucl»~nsiens areapplicable oiilyto. the trade in heavy 148 Collllilil/It’lCdl7l07l5. articles of small value. Equally salutary results might however be obtaini- ed by modiﬁcations of thecharges on the other principal division of the- c'on:imerce of the coi=rntry——that which is rendered by its value an object for -the_~competition_of rival worlrs.. But the exarriiiiationof_.the subject with. ‘reference to the latter division would, from its complication, be much less susceptible of receiving a popular form. ,_This and other views of the sub. ject, which have always to be considered in any attempt to establish a cor- rect tariff; ’are examined in considerable detail in my “Essay on theyLaws of Trade,” where the methods to be adopted to obtain the greatest revenue whichthe work can possibly extract from the commerce of the countryjg fully exposed. It is not possible to repeat liere,.inv,the narrow space which we can now appropriate to the subject,.even the most important of the prin- ciples to be regarded in the administration of our public works, which I have there attempted to develops. The glance which IS-~ here directed to the question is necessarily confined to a very few prominent points. , To establish a tariff of toll for all ,articles,. on sound principles, requires a certain intimacy with the statistics of the line, and a proper ac.q,ua.intance with the laws by which the tonnage and revenue are-govierned. This knowledge cannot be obtained intuitively; and a.cor.rect.ta:_riff' cannot: be de- vised, as those on all our improvements are, by the mere conjecttiressoﬁ the parties to whose discretion such subjects are usually referred. ' SECTION V.-—-Geneirail Lawsof Tm-ale. 18. There are some facts of a general c'ha'racter relating to this subject which are susceptible of a most rigorous dentmnstration, that may be here proﬁtably repeated. It has already been shown that a great loss of trade and revenue is sustained in the manageinent of ptiblic works by the adop~ tion of a uniform rate of assessment. In the exaniplesadduced, this re sults from over charges, which, under such regulations, invariably have place in some part of the line. It may be shown by a legitimate course otl argument, that however we depart from the charge which will yield the- greatest revenue there will be an increase ordiminution of tonnage, and, of: course, always a decrease of revenue. I If the departure be an overcharge, the tonnaige will be rerlncerl (L quantity directly pit/portionnl to the value: of the overcha7=g‘e,'an(i’ the revenue proportional to the square of that cle-- pwrtti/re. ‘ ‘ l , * Nothing can prove more conclusively the danger of submitting so im-» portant a subject as the preparation of a tariff; to the uncertain guide of” conjecture. For, if we err ten mills in the charge which we establish for any] article, the loss will be onerhundred times greater than it" we err but one- mi . i i 19. It is usual to assume that the charge for toll should be proportional to- the distance thearticle is carried——-that it should be greater fora great dis-r times than a short one. But we have already seen that, on the contrary in most cases, the greater‘ the distance the article is carried the less should be the aggregate toll upon it. (Art. 13.) . 20. It is common to suppose either that the tariff’ of toll is independent of the cost of freight, or thatthe higher the expenses of carriage the great- er should be the charge for toll. But, on’ the contrary, the fact is ‘suscepti- ble of general and easy proof, that the higher the aha/rge for freight on-the line, the lower must be the toll ; and also that any increase of the cost of freight will at the same time diminish the tall or profit on the article, and increase the whole mg: for its transportation. i 1 21. The charge for toll is ta-lso, assumed, _in the ordinary establishmentsof tariffs, to be independent of the mode By which the trade approaches the line; and, for many articles, this is true; but, for others,’ it is an ascertained Cornmurtications. 14-3, fact, susceptbile of easy demonstration, that if they are brought to the {work by a common turnpike a higher toll should be charged for their passage on the improvement than if the same articles reach the work by a railroad, and, a fortiori, than brought by a canal. . y p 22. Where the object is to obtain the greatest possible revenue, it is a general law, susceptible of satisfactory proof, that the charge for toll should not exceed half that charge which would exclude the trade from the line. It may be shown, however, that, although a higher charge than this can never be advantageously adopted, itmayfrequently be reduced to three-eight: of the sum which would cause the exclusion of the trade, with avery ben- eﬁcial efiect on the tonnage, and without leading to any sacriﬁce on the score of revenue. « 23. Another fact, which may be derived immediately from thepreceding is, that where the most judicious charge is levied, the tonnage of the line will be one-half of the tonnage which would be obtained if no toll at all were exacted. ; 24. The charge for toll has already been shown to depend in part on the price of freight; and it is an established law that if the cost of freight be increased or diminished by any modiﬁcations ofthe Work, or the system of transportation adopted on it, the toll must be increased just half as much as the freight is diminished, or diminished just half as much as the freight is increased. And it is further susceptible of demonstration, that the in- crease of revenue which will follow a general reduction of the charge for _freight will at least be equal to the arithmetical mean between the mines of the tonnage before and after thereclnction, multiplied by the amount that the ﬁcight is reduced. In other words, if the trade of the line he one hundred -thousand tons, and the freight be from any cause reduced $1 per ton, and the tonnage thereby increased ten thousand tons, the revenue of the work will be increased more than $105,000; and this result will have place simultaneously with a reduction of the whole tax on the trade to the amount of $50,000, and the corresponding augmentation ofthe tonnage. t 25. The fact is not usually recognised, that the toll, and tonnage, and re- venue, are all- more or less dependent on the length of the line of the im- provement. It may, nevertheless, be easily proved by a general demonstra- tion, that the tonnage, the charge which may be leciedyer ton per mile, and consequently the revenue will all receive an increase by 41; reduction of the den th of theline of transportation. So that if the toll be judiciously es- "tab ished on any given line, and any material, change of location afterward be made, by which the distance, or cost of freight is diminished, there must be a certain increase of the charge for toll, from which an augmentation of revenue will necessarily result. The value of this increase of revenue is equal to the whole annual tonnagelof the line, multiplied by the actual cost of freight through the distance saved———and, considering only the value of the trade, it is therefore worth, to reduce thelength of the line, the capital of which the interest is equal to that sum. _ 26. In the arrangement of the charges in a tarriﬂ“, there is no subyect of greater importance, for some articles, than the positive, and for others, than the relative, value of the mart. From the positive value of the article, is de- termined the tax which one division of thetrade can sustain ;. and from the relative value is in part deduced the proper tollon allcommodities for which -other works are competitors. A permanent change of the relativelstanding of the mart, Wight. there‘ fore, to superinduce arnodiﬁcation of the tolli, .A,ndii-t,mt1.Y b9 35-">1lY Show" that if the relative value of the market--»-by which is intended its value com- pared with that of the rivalfinart--be increa-sedt-any given sum. we shall ﬁnd :y 50 ‘Communication. the corresponding increase of toll per mile proper to be made, by dividing that increase "by twice the length of the zmprooement 271. miles. If, for in. stance, the value of Philadelphia as a mart for tobacco, compared with the value of New Orleans in reference to the same article, be. from any cause, -increased $4 per hogshead, and the distance from Philadelphia to Prttsburg be four-hund_red miles, then, I say, the toll on tobacco on the wholecentml line of the Pennsylvania improvement, should be mcreased a half-cent per ‘ton per mile. _ _ It is also easy to demonstrate that, at_the same tune, the revenue well be antgmenterl by any increase of the relatz2:e value of the market, an ammmt obtained by mnZtiplyi'ng the orzgznal tonnage odztlecl to half the zncrease of tonnage consequent on an improvement of the market, by the encrteased M. lue of the tonnage at the market. . - A . ' — It is shown, in fact, that whatever circumstance occurs to increase the value of the property sent along an improvement, to the holder of the pro. party, will cause a certainincrease of tonnage, of which the measure can ‘be obtained, and a simultaneous augmentation ofrevenue equal to the whole increase of its value; and that rt»/tntever u7tnecessm'g/ tax as levied on the trade, is at lettstso much deductecl from the revenue of the improvement, If. for instance, the engineer in making the location permit his line'to' be one mile longer than is essential, he will thereby cause to the State or com~ pany an annual tax, or equivalent loss of dividend. equal to the whole an- nual expense of transporting the ‘whole trade of the country through that mile. He incurs, at the same time, the responsibility of reducing the ton- rnage of the work, and of injuring, to a certain extent, both the country that supplies the trade, and the emporium which receives it. If he embarrass the line by an unnecessary grade, or any other impedi- ment which involves a similar increase of the charge for freight, he is re.- sponsible for the same result; ‘and, before adopting such a measure, is bound to compare the value of the difliculties to be avoided, with that of" these in- evitable consequences to the future trade. » 28. It is an--error, and a very frequent one.-to suppose that the tollis in any manner dependent on the cost of the work; or ought, underrany cir- cumstances, torbe directly proportional to the value of the article. i It is, however, not uncorn'mon.to» assume, that it ought to bear some relation to the cost of "construction; and there are tariffs of toll in the data for the cal- culation of _which» the value’ of the commodity is in principal, if-not the only element. It is not a little singular that, afterencountering an expense of hundreds of millions for our public works‘, the tariﬂs by which they are to be sustained should be entirely ruled by considerations which, however plausible in a superﬁcial view, have no legitimate relation to the question. For one division ofthe trade, it is not the positive value ofthe commodi- ty, but the differience between the market value and the cost of producjtion; and for the other, the diﬁ"e.ren‘ce‘het\veen the value ofthe article at the mart of the improvement and at that of its rival, by which the toll is inﬂuenced. And this inﬂuence is only partial. The value of the article. taken in any sense, ‘is only a part of the data by which the true charge mustbe detai- mined. .29. It is by no means the .intention here to, attempt a general anatl‘ysi‘sv0f this most important subject.‘ ‘My object, as alread«y'announced, has"beer'r‘to show that, under certain pcircumstances, a marked increase of trade and res venue may he obtained on all our public works, by simply reducing? the‘ changes; ‘and that such modiﬁeh1tto.ns of the tax.‘leevied on the co.mm«uen.i;tyi~s rentlered Irnperativeby the ﬁrst‘p‘tin‘ciples of equity, If ' I have st1c‘c‘»eed‘e'd in making this truth perfectly apparent, the design’ of these pages will hie fully accomplished. , Commun_ication:. 145 1 I scarce hope to have satisﬁed the reader a discussion so brief and popular, that to enable a company to take the full advantage of its position, and obtain the highest degree of success of which their enterprise is sus- ceptible, demands a careful and close investigation of the laws of trade in reference to every branch of the subject. To appreciate the importance of this course, requires that the mind should have investigated such questions sufﬁciently to estimate the consequences of its neglect. To lrnow the value of establishing the most correct tariff, we need to know what we are likely to lose by the adoption of a conjeetural ‘or empirical one. - ~ This subject, though usually taken under other auspices, is peculiarly a professional study. An intimate acquaintance with the principles which » govern the trade of an improvement, is a department of knowledge which is essential to the engineer in the location of his line, and the establishment of many of the plans of hiswork. His ﬁrst duties, whenlproperly dis- charged, compel him to become the most intimately acquainted with the productions and statistics of the country, and the information acquired in the accomplishment of these labors, ought to be turned toaccount in directing the futu re administration of the line, The preparation of the tariff is, or ought to be, the peculiar province of the engineer. For, though there maybe many considerations of policy. which should have a-certain weight with those whose final action is requi-r site to carry his recommendation into eﬂ'ect—and which may frequently render it advisable to modify the charges. which an a-.priot'i investigation may indicate to be proper, where the. questions of trade and revenue only are under r:onsideration,—still, it is not less important that thetariﬂ‘ should first be correctin itself, that some estimate may be made of the effect that will be felt when such political modiﬁcations come to be admitted. And, . withal, -it is difficult to conceive what motives of policy should induce any material departure from those limits which the administration ofjustice, the . promotion of trade, and the augmentation of the revenue simultaneously recomrnen-d. LE COUNT ON RAILVVAYS, “ Uniformity in the width of track” ﬁnds as little favor on the other, as on this side of the water. When the contracts along the line are fairly at worlt, one ofthe first knotty points which the directors will have to decide on, is. the width of the rails, their shape, the length of their hearing, and the form of their ‘chair. The width between the rails has only lately become" a subject of dispute, nearly all the railways prior to the Great Western, having been laid down 4 f’eet8-3; inches apart. Mr. Brunel has extended ittoseven feet, the Irish railway commission recomzncnd six feet two'inches, several ofthe Scottish railways are laid down at five feet six inches, "in fact, the variations run from four and a halfto seven feet. , The question ofthe stability of the carriages on therailway may be left out of consideration in looking at this matter, because the machlnery Wlll always require sufficient space between the wheels to insure this. Now, as 4 feet 8% inches are found to be enough for the good performance ofan engine. which with 51} feet wheel, will go on it level upwards of69 mrlesan hour, as with 5 feet wheels, Marshal Slout, on his visit to Liverpool just after the ‘-Queen’s.coronation, was taken over 10%,! miles of favorable ground on the Junction Railway within 10 minutes. do as an engine has gone60rn1les Grand. an’-noour on the London and BlTmll'.t,Q‘l1‘.'lm Rail\vay,_,.upan inclined plane. is itgwise or prudent to malts any change at all“ find Will ‘my add‘“°“a1 ;_5-gt Ra;ilway.¢. speed, which may be gained by increasing the width of the rails and the «diameter of the wheels compensate for the greater. expense of the outlay, which will constantly be required tokeep the road in order on account of the increased weight? This will receive light from the experlments on the Great Western, but will not be fully decided until it be tried on the Irish or some other railways, as Mr. Brunel’s rails are altogether.diﬁ'crent from most, [others in use. The plan recommended by the Irish railway commission- ers, of puttingthe rails fartherapart but _not.widening the carriages, mere-r -ly making the wheels run outside the bodies, 18 a good one in some respects; ‘shut it would add to the expense of the works considerably, and the result would be exceedingly questionable. _ It must not be forgotten, that, where a different width from that in com- umon use is adopted, the railway on which it is usedbecomes isolated. None ‘abut its own carriages can travel on it, and they can travel on no other line. "This alone will, in most cases, be a serious objection. For our own parts. we should say, let well alone; wait for more experience; We are yet infants -among railways, and we ought not to innovate on that which has proved to do well, until we become giants. The majority of opinions, however, are beginning to lean towards some increase ‘in the width, although there is every diversity in the quantity which practical men thlnlc necessary. Cer- tainly the machinery under the boiler is compressed into its minimum space, and more room for it would be a great advantage, if It. does not in.- d‘-uce an incommensurate loss in other ways. b With respect to the form of the rail, it can be proved that a ﬁsh belly has greater strength, weight for weight, than any other. A 60 lb. ﬁsh belly at three feet bearings, rolled with a lower web, would be the best form of all; and this has been effected, as the original Liverpool and Manchester ‘rails had partially this shape. The question, however, must be looked at in conjunction with the length between the supports.~ We have given below ‘those forms most approved of in practice, and have added" that in use on the Great VVestem Railway, which is however light, and does not stand well, three feet having been theoriginal distance of the bearings. Fig. I is the old Liverpool and Manchester rail, laid down at three feet hearings; weight thirty-three lbs. yer yard, with square joints. This rail mistrclled with a lateral swell at the bottom, which on one side was con- tinued the whole length, but on the other did not quite reach the chair-— One side of the chair was cast with a cavity, into which the lateral swell ﬁtted, and the opposite side had a nearly similar opening, in which was driven an iron key, shaped like a. wedge, which, entering in a longitudinal direction, not only forced the swell into the cavity which was formed to re-‘ ceuve it, but by this means, at the same time, kept the rail down in the chair. Fig. 2. Losh’s patent rail, in which he sought to gain a still more pow’- eriiul. mode of keeping the rail down in the chair, bvhaving his key taper’-« ed verticall y as well as longitudinally. so as to act ah a wedge dovvttwardﬁi as well as in the direction of itslength; whilst, at the same time, the neces- Raxilwag/3. 353 expansion and contraction is allowedto take place. A key on each sary _ _ 9 _ ‘ side has also been used with this form of rail, still, however, the keyswete always found to work loose. Losh had also a projection rolled on the hog. I Fig. :2. "L" ‘Z M‘ ’i;»:41%—-*_ M.-2" T % -—...$..—..._......._o—« ...... .. ................................... .. tom of his rail; at.the part which lies in the chair, where a corresponding cavity was cut to receive it, so that the effect of expansion or contraction. would have a tendency to raise the rail in the chair, and thus wedge it tight- er. The upper part of the notch for receiving the key in the chair was also formed with a slight curve, to allow of a small motion in the block, and the rails were made with a half—lap joint, formed not by cutting the middle rib of the rail, but by setting it back, so as to preserve. its whole strength.-— They were laid down at three feet bearings, and weighed forty.four lbs. per yard. but of course were not restricted to that, or to any other weight. Fig. 3. The London and Birmingham ﬁfty lbs. ﬁsu bellied rail. This was laid down atthree. feet hearings, and the half-la‘p joint formedby set- tinp back the middle rib instead of cutting it, in the same wayas Loshfs mi . It was keyed downby a pin going through the side of the chair in a c direction sloping downwards. The end of this pin went into anotch in the side of the rail, at its lower parts; the pin was forced tightly in by an iron key acting through the chair, andlalso through a hole in the pin, by ‘ Fig. 3. which it was driven both in and downwards; and the end of the key being split, wasthen opened, to prevent its being shaken loose. Mr. Stephenson has a patent for this chair." The rails did not rest on the bottom of the chair but on a loose piece of iron, the lower part of which was the segment of a circle, and the upper part ﬂat, and of the same width as the middle rib of the rail; and this worked in a circular cavity in the chair, so as to allow a motion when deﬂection took place in thetrail. These rails had no bottom webs. . t . Fig. 4~_is the St. Helen’s»and Runcorn rail, with a bottom web. ih.av»i‘hg"~a. .3_emicirc1_1lar base. These rails are forty-two lbs. per ard, and were laid down at three feet bearings. A wedge on both sides 18 used. which acts. Fig. 4. 1‘ W p 20 154 Railways. downwards as well as sideways, from the opening in the chair to receive it being narrower at the top than at the ‘bottom. _ Fig. 5 shows the parallel rails laid downon the_Grand,.'_lunction, and London and Birmingham railways. The left hand one is sixty-four lbs, per yard on the Grand Junction. The right hand one is the London and Birmingham seventy-ﬁve pound rail. Rails of -this kind are laid on.sev- enty-ﬁve miles of that railway, and were intended _to be at live feet bearings, hut proved a complete failure at that distance, which had to be reduced to three feet nine inches. The left hand one was intended to be at four feet Fig. 5. bearings. These rails were both laid down contrary to the opinion of the engineer, Mr. Stephenson, and have entailed a vast expense on that compa- ny.‘ They have wooden wedges. . Fig. 6 is the Great Western rail, laid on longitudinal timbers, andforty four lbs."per yard. Felt is laid between the rail and the timber, and the former is fastened down with screws. It has been found deﬁcient in strength" for the heavy engines used upon that railway. . Fig. has been frequently adopted on railways formed with longitudi- nal bearings. It is spiked down to the tim- i Fig, 7, ﬁgs, and requires _no chair. -The weights . / / i e varied from thirty-ﬁve to sixty lbs. per %’ yard. Sometimes the spikes have not‘ gone // .'- . ‘ through holes in the rail as in the ﬁgure, § but have been driven in just outside each edge of the rail; in which case they are ' ° made with large heads, which come down and clip the rail ﬁrmly to the timbers. . . The London and Birmingham railway companies, after a long discus- 310D. decided to try four and ﬁve feet with a parallel form instead of a ﬁsh- belly. Which, requiring one-third more height in the chair, had, in addition to other disadvantages, that of being more liable to wring the chair from the block, which is found in practice to take place directly as the height of the chair. The block is also more loosened in the ground by a high chair and the cbutinual repairs arrising from this loosening, amount to one-half Railways. 155 the wages expended in repairing the way in general; hence every means of diminishing such a heavy item, which can possibly be devised, should be put in practice. As usual, where all was theory, there were considera- ble diversities of opinion. Those who wish to enter more at large on this subject, may consult Professor Barlow in favor of lengthening the bear- ings, and Lieut. Lecount against it. As the matter has had a fair trial, it is only necessary here to state the results. d On the Primrose Hill contract, which was. laid withfourifeet bearings, it was found much more troublesome to keep the permanent way in order, than with bearings of three feet. With the four feet bearings, it was found, that, in a very short time, the rails were put out of gauge, the width con- tinually increasing, until it became absolutely necessary to readjust the whole. This was observed in a very marked manner with a part of the line near Kilburn, which had been recently laid down. , On the Harrow contract, from the crossing of the Harrow road to No. 12 cutting, the permanent road was used for conveying away the material from a side cutting. The traffic was of course considemble, but not by any means such as to account for the absolute difficulty which the contract- ors had in keeping the railway in guage. They were obliged to put sleep- ers at the joints in addition to the regular number of blocks, which of course kept the rails in guage at those points; but notw-ithstanding this, the inter- mediate blocks moved outwards. When the engineer’s attention was first called to this position of the permanent way, he was inclined to think that something might be attributed to the blocks being placed anglewise; but after giving this port of the subject his careful consideration, he felt satis- ﬁed that the position of the blocks,was at least as ﬁrm as the square posi- tion; and he felt confirmed in this opinion, by the fact, that, in another por- tion of the line near Kensal Green, where the road was laid in the ordina- ry manner with blocks three feet apart, and placed anglewise, and where locomotive engines had been constantly running for eighteen months, there was not found any greater tendency to a motion outwards, than when they were laid square to the direction of the rail, in the old manner. If, there- fore, the diagonal position of the blocks had been defective, this was the place to try it; for the quantity of material conveyed over this part of the permanent road in wagons without springs, and with heavy locomotive en- gines. was very great indeed, and under circumstances well calculated to detect any marked difference in the construction. On the Berkhempstead contract, where ﬁve feet bearings were in D397 and were a locomotive engine was at work, the contractors made. heavy complaints of the greater difficiilty they had experienced in keeping the rails in guage than there was with the shorter bearings. In fact, in the‘ eighteen months prior to ‘June i837, the three feet rails in some parts ofthe line, had more work than they now have, where the line is open; yet they stood it well, while the ﬁve feet have been so put out of gauge by one day’s work, that the wagons had to be stopped till one and two additional slee 4' ers for each ﬁve _feet could be laid down. and even then they were but indif- ferent; and similar complaints having come in from other quarters','toget'h-'*, or with the fact that the ﬁve feet bearings on the Liverpool and Manches- ter railway were found to cost double the sum for keeping the way in ‘re- pair that was required with three feet nineinches bearings, the whole ques- tion had to be opened again, and the directors resolved to shorten the bear- ings from five feet to three feetnine inches. , ‘ Th'i's- lateral deﬂection is of most serious importance, when We ‘recol- lect that the rails being out of guage will throw thetrams 05 the 1m9~'* The lateral Blows which an engine may give are such, that several chairs‘ 15.5 T T Raiilwag/5. in succession ‘have been broken or knocked oil‘ the blocks and sleepers; and the absolute weight passing over any one rail may lie_faii'ly taken as three times the nominal weight, for the effect from ll,1rcl3l.Ug has been experl-A mentally found with engines having three tons weight ‘on each. of the driving wheelsto increase that‘ iveight to seven tops; besides which, we know that four wheeled engines, for instance, will, in practice, he frequent- ly running on three wheels,no railroad being a perfect plane; and_when these three points are in th: aclzt of shifting, the engine during that time is onl su orted on two w ee. s. ’l"he ilijdixure produced by this weight perpendicularly has also this bad effect, that the engine and train are constantly ascending an inclined plane in practice, although the railway is C0t]S1(lt‘.r~e(ii1SleYel, and of course where the railway has an inclination, that inclination will be proportionally in- creased. This was first pointed out by Professor Barlow, and is an impor- tant fact; for on the short planes between each block or sleeper caused by the deflection of the rail, the gain in descent is so insigniﬁcant, that it may be entirely neglected; consequently the engines and carriages. are constant- ly going up an inclined plane between each. support of the rails equivalent to the central deﬂection divided by twice the distance between the supports. This is,'from calculation, ascertained to be as follows, viz. 2- Increased Power Bearing distance. Deflection. Equivalent planes. require per ton. Ft. In. Inches. 3 0 '0524 1 in 3000 '75 lb. 3 9 ‘O37 l in 2432 '92 lb. 4 0 ‘O41 1 in 2341 '95 lb. 5 0 ‘O64 1 in 1875 1'20 lb. 6 0 '08? 1 in 1756 130 lb. Although the deflection of rails will generally be diﬂlirent from the above, and the increase of power required to surmount the consequent planes will also require considerable modiﬁcation to suit the action of lo- coinotive engines, which depend upon so many other circumstances besides the action-of gravity ; .yet the fact remains the same, namely, that with de- flection there is a consequent loss, and the subject deserves much more con- sideration than it has received, especially as we know that ﬁsh-bellied rails do not fail in the middle, but about eight inches from the supports. A rail ought not to act asa spring; but as this to a certain extent must be the case, it should be made to do so as little as possible. A spring should only be used to get over an obstacle where one must be met, but if the rail acts as aspring it creates an obstacle where none existed before. We must also remember that when deﬂection becomes permanent, fracture begins, as we break a thing we are not strong enough to pull asunder, by bending it backwards and forwards. In fact, the experiments on deflection havehith- erto been such that they have merely served to unsettle all opinion, and to place one set of deductions in opposition to another. The mode of estima- ting this element by two wheels on an axle, loaded at their peripheries, arid oscillated on the rails, is one which well deserves attention. In all cases. the ﬁrmer the rail is fixed to the chair, as respectsrising in it, the less will be the deﬂection. Of course it must always have a motion in the direc- tion of its_length to allow for expansion and contraction, the force of which will_VaTY1n good or tolerable iron from nine to six tons per square inch of section. The expansion of a ﬁfteen~feet rail may be taken at 00126 inches for each degree of Fahrenheit, and as it will not be safe to take less than Railways. ' 157 ~90°'fot‘ the range of our climate, this gives 'l134 inches for the total, or 10567»a»t each end of such a rail. i _ In-order to understand the action which takes place in the case of a de- tﬂected ~rail when a heavy weight passes over it, we must know the effect of :gravity at the velocities used on railways. For this purpose, if we take 'thrce, four and ﬁve feet beraingsias those which seem at present likely to be the limits, the following table will give us the. time occupied in going -over half the rail in each case; and from this we shall be able to ascertain athe effect of gravity during that time. ‘ A 1 » _ . _ _ _ _ Parts of a se- Parts of a se- Parts of a se- Velocity in . Velocity in Velocity in condin which cond in which cond in which miles per yards per inches per 18 inches are 24 inches are 30 inches are hour. minute. secon . - passed over; I passed over. passed over. 10 ‘2.93'33 ‘ 176 l-9‘8 1-7'33 1-5'86 20 58666 352 1419-6 ,1—14'7 1-1l'73 30 87999 528 1~29'3 1-‘.32 l-l'7'5 ' 40 117332 704 p 1 1-39'l 1-293 1-23'47 50 , 146665 880 1-489 1-367 1-293 60 175998 1056 1-58'7 1-44 1-35‘? 70 205331 1232 1-68'4 1-513 1-411 80 234664 1408 1-782 1~58‘7 1~46'9 90 263997, 1584 1-88 1-66 ' 1-52'8 100 29_33'30 1760 _ 1~97'8 1-733 1-58-7 Or putting Cb for the velocity in miles perihour, 1: for the velocity in , t ;yards per minute, and v"for the velocity in yards per second, we have __ 1760'a__ 9.333 e ,_ lﬂl-w__ _ 8 v —- 60 -2 at M v — 3600~-48 8a. And in the table, taking either of the three right hand columns, accor- dtngto the length of bearing, for instance the eighteen-inch column for a three feet rail, we havethe number of inches through which the-engine or any other body would fall by the action of gravity in free space, in the time which it takes to pass over 18 inches atthe given velocity, by the for- mula s=t9-193, where t is the time in seconds, and s the space in inches. Thus at 20 miles an hour, with nthree feet rail, where 18 inches are pass- ed over in T{,-.; of a second, the engine would fall during that time 1 ~1 2 1 t 193 ., , ‘ -193 =‘3‘§'I_‘l"6"'l.93 '-=§§-4?-1-(-3~"—='5, or half an mch. Again aty30 miles an hour, with a three feet rail, 18 inches of which are passed over in 3%., of a second, the engine during that time would fall 1 9 , 1 193 . (§9—,3- -193 =-8-5§_-4-g—'l93 ==§-sgq-g-='225, or not qu1te aquarter of an inch. , And denoting by t and s theitime and space as above, _we have converse- 'ly, knowing the space an engine would have to fall, for instance, through a bad joint, the distance the engine would pass over without touching the Jower rail, by the formula __ 1 s t" T9'a“' Thus when .s==’225, wehave A "225 .‘._......_ V 1 t= “T§§’=J‘00ll66——- '0341-— z9_3 of ‘a second, in which, at30‘miles an hour, we ﬁnd by the table theﬂeuginle _ .158 Rail-way/s.—E'i'ie Ccmail Enlwrgcmeiit. would pass over 18 inches ofthe lower rail without touching it, describing. in its fall a parabola modiﬁed by the effect of the Springs 0!1~tlle engine. This has been put to the test of experience by bending a rail nearly half’ an inch. and then painting it. An engine and train of carriages were then run over it, none ofthe wheels of which touched the paint for 22 inches, This affects a railway in three ways. First, ‘when. the engine has to fall, through a badjoint, the rail which it leaves being higher than the rail it is coming upon, the increased momentum from the fall will here occasion a larger deflection than ordinary, and a consequent inclined plane against the engine, from the time it comes on the rail till it passes the next chair. Sec. onaly, when a rail is permanently bent, where the resistance on the second or rising part of the rail will be less than in the first case. And ‘thirdly, when the: rail is simply deflected by the weight ofthe engine. and restores itself to its original level when that Weight has passed; here the effect will’ be least of all, the rail taking the form of a receding wave before the whee}! and a following wave after it. In the second case, where the rail is permanently bent, the formula for the space the engine would fall will be ‘-H 193 is sf L _ ,. where H is the height of the plane, and L its length, s and if being as be fore. For instance, if the bend ishl of an inch in a 3 foot rail, we have ‘I 1 1 . _ . s==«1-g5 ‘I93-Egéjzg-='00l25 of an inch, at 30 miles an hour, ~ 1 H . t . ’ . ands:-1-8-6193‘-5§5:~jl—-6—='0O2I8 of an inch at 20 miles an hour, or E}, of an inch at 20, and gm of an inch, at 30_ miles an hour, ‘would be de~ scended by the engine. by the effect of gravity, in the same time that steam .-and gravity together take it along 18 inches of the rail. _v V ‘ Let us next suppose we have steam enough to carry the en-ginealong at :a velocity so great, that gravity _will_ not bring it down the '1 of an inch perpendicular, whilst steam carries it along the 18 inches horizontal, we .-shall ﬁnd this velocity to be at and above 44 miles an hour, for it takes 1%- of asecond for a body to fall one-tenth of an inch by. the effect of gravity. and 73-3-”: 18 in. =3600”: 44 miles; hence at 44 miles an hour, and at all velocities above it, the engine, after arriving on thle rail, bent one~te.nth of an inch in the middle, and forming two planes, wil no longer touch the rail till after it has passed the middle of it, and velocities of 60 miles an hour have been attained. A — (To be continued.) Erma CANAL ENLARGEMENT.-—A series of articles on this subject, have ‘been lately published in the Railroad Journal, under the signature of Ful- ton, which appear to us to be both_timely and appropriate. Other numbers are yet to follow. The writer calculates the whole cost of the enlargement, including damage and loss ofinterest, at $40,000,000 it! He shows from the annual Reports of the Comptroller, that in consequence of the gradual destruction of the forests in the neighborhood ofthe canals, the down tonnage has fallen off within the last ﬁve years to the extent of 140,000 tons, will not, for a long time to come, be made’ up by the increase of agricultural ' products; thateven double locks are not now wanted; and that any enlarge- ment beyond adding 12 or 18 inches to the banks, will be money thrown -away.‘ He complains of the impolicy and injustice of making private en- terprise, asjdeveloped in railways along the line of..the'cana1, tributnrg/‘:10 the State, as a means of defraying the interest on the enlargement. He re- Lbcomotivé Engines. 159 buts the doctrine heretofore maintained by some, that the effect of the en- ilargement will be to reduce transportation 50 per cent. Persons interested in the subject, as every’ citizen of the State is, either directly or indirectly, will do well to refer to the articles themselves. We perceive, as yet, no «decisive movement in the Legislature, having for its object to arrest the enormous expenditure which is being entailed upon us. The subject will be thoroughly scanned by posterity——of that be assured. Forty million dollars, or twenty millions, ifsuch a debt is incurred for the proposed en- largement, will be an incubus upon our credit and resources, whi'ch it will not be easy to shake oﬁ'.—Jour.iof Commerce. LOCOMOTIVE ENGINES.-—-The statement of the performance of the L0- comotive Engine '“ Minerva,” on the Philadelphia and Readingnai-lroad which we take from the United States Gazette, will be found interesting and useful on account of the business like manner in which it is prepared. More of the Philamlelp/Lia Engz'ncs.—-We have great pleasure in pre- senting our readers with the suhjoined statement of the ‘performance of the " Minerva” Locomotive Engine, built by William Norris, Philadelphia, on the Philadelphia and Reading Railroad, with a train of 85 loaded cars, January 15, 1840. ° M1 '6' ":3 = ' ,_; 3 V gr‘? '§—§ pig; d3 gag nsmnnxs. . 2 as h. mac 3:3 cifct’ z‘sc%:.3:.-;:3§r Between 1» Reading & . r l Pottstown, 54 227 l I 322 0.4 17.5 113.8 6.5 4.3 5.1 W00‘? d593' Pottstown & ‘ . l we ’ W‘ Phcenixville 62 2610 56 329 0.65 13.0 40.2 3.1 2.5 7.4 do. do. do. Phosnixville ’ , i , ,&inc,p1ane,,§.E3 3502 47 E9 1.14 24.0 59.5 2.5 9.1 15.3: Woodcreen Total, P 4 44 1537 2.19 54 5[213.5: 3.92“ 27.8 Two quarts of oil only were used by the Engine and Tender in the trip, including oiling before starting. Nett weight of freight 2163 tons gross weight, 350 tons or 784,000 lbs. P ‘ In the above statement the tons mentioned are grass of 2240 lbs. ‘Weather clear and cold, rails in good order. Weight of engine, empty, 23,040 lbs. With water to second cock, 25,730 “ With water, fuel, and two men, 26.300 “ ‘On four driving Wheels, ' A] 5,150‘ “ -On driving wheels, with water and fuel, 17,450 “ On driving wheels, with water, fuel and two men, or in run-. ning order, f 17,900 “ Her tender holds 504 gallons water. . The engine started the trainrof 85 cars three times on a level; and on one occasion in a curve of 955 feet radius, without any straining or d1fﬁcul- ‘ ty, and at various times attained aspeed of 14 miles per hour through some curves of the above radius on a level. 4 V The quantity of steam generated, when common dry oak wood was used was more than sufﬁcient to supply her cylinders; and from the surplus quantity which escaped- from the safety valve, I have no doubt she could 160 Meteorological Record, for Nov. and Dec. 1839. have taken 20 more loaded cars, or 90 tons, had they been ready',.and‘with: out any injury to her machinery. _ Signed, G. A. NICOLLI. Superintendant‘ Transportation Phlla. and Reading Railroad: Reading, Pa. January 18, 1840. For the American Railroad Journal. and Mechanics’ Magazine. METEOROLOGICAL RECORD FOR THE MONTHS OF NOV. and DEC.. 1839. Kept on Red River, below Alexandria, La.. (Lat. 31.10 N., Long.. 91.59 W.) 1839, THERMOMETER. . REMARKE Nov_ Morn. Noon. Night. Wind. VVeﬁth~ "" 55 70 55 calm cloud y light shower forenoon g 55 5g 67 .. clear lioht showei-_atn1 ht 3 62 53 55 .. ~- clhudy morning c ear day 4 66 74 75 s ‘nigh - - all ‘day 5 63 69 58 NW high - - “ 6 46 .62 51 W ' ' _ 7 .49 54 50 Nw - ~ white from 8 36 60 so calm -- :: 9 38 62 52 -- -~ _ _ _ 10 41 7-2. 65 -- -- rain in the night 11 65 71 64 w -~ , 12 46 173 67 -- - - foggy morning ' 13 47 75 67 sw cloudy ram 1n the evening 14 45 75 68 - - - heavy showers_ull day 15 51 53 51 NW morning, 8V6!lll'lg clear 16 44 53 50 Na clear 17 45 es _e1 calm foggymornimz 19 51 68 . as w -- 20 52 52 50 N cloudy _ . _ 21 45 4.6 42 mg -- ' rum evening and all mght _ 22 40 42 42 .. -- “ steady ull day and all night 23 40 41 40 N -. all day 24 38 44 48 NW - - morning, clear day 25 30 31; 30 Nhiglx -- all day _ 25, 23 so 37 calm -- “ [mghu - NE ruin i ht'showc_ars and drisling all_dny and «all. 28 48 52 53 calm -- light rialing ram all day and all night 30 44 1 58 52 :- evening clear D 47 59 56 ......... mean temp. of the month 54. cc 1 44 48 47 callm clear foggy morning 2 45 60 54 NW lﬁht - ~ 3 32 61 52 calili -- white frost ‘ 4 32 56 52 .. - - . “ ' 2 :3 48 49 -. cloudy Vgllltfi frosktl, rain in tlhe evening ai(1id.nlight _ 54 50 .. -- 1 un er s ower in t e mornin ms in rama 7 33 59 52 . . clear white frost g‘ [a l dnyr S 34 45 42 Nw high - - “ 9 28 52 55 sw - - “ 10 34 62 60 . . . . “ 11 55 58 52 NW . . “ 12 31 50 46 w " 13 32 52 60 sw cloudy all day 15 35 50 45 calm clear white frost 17 34 56 44 NE .. “ 18 40 50 55 1 1 d 19 38 48 50 °‘.‘.’“ c y -- ' 11th 1" ' l r 21 46 48 48 NW clear rain :1 a orenoon, evening calm and c on 23 40 40 40 NE cloudy rain afternoon and ullnight 33 32 50 45 - - clear white frost 27 38 53 50 - - cloudy rain all the forenoon, cloudy all day 5 44 ‘ - clear white frost 28 4-2 54 45 W .. “ 29 32 50 48 calm “ so 45 53 531 " ‘ - 31 40 34 35 cgﬂigy ram and thunder at night 39 56 48 mean temp. of the month 48.
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Title: American Railroad Journal July 25, 1846
Date: 1846-07-25, 1846-07-25

Title: American Railroad Journal May 30, 1846
Date: 1846-05-30, 1846-05-30

Title: American Railroad Journal January 15, 1848
Date: 1848-01-15, 1848-01-15

Title: Minutes of the Concord Baptist Association
Date: 1842
Description: Convened at Bethel Church, Caldwell Parish, Louisiana on the seventh, eighth, and ninth, of October, eighteen hundred and forty-two

Title: Speech of Mr. Horace Mann, of Mass.
Date: 1848-06-30
Description: Speech on the sovereignty of the federal government in the territories and the implications of that power regarding slavery.

Title: American Railroad Journal July 3, 1845
Date: 1845-07-03, 1845-07-03

Title: American Railroad Journal May 16, 1846
Date: 1846-05-16, 1846-05-16

Title: American Railroad Journal June 20, 1846
Date: 1846-06-20, 1846-06-20

Title: Speech of Caleb B. Smith of Indiana
Date: 1848-07-21
Description: Speech About Veto Power. Delivered in the House of Representatives of the United States

Title: Minutes of the Fourth Annual Meeting of the North Liberty Association of United Baptists
Date: 1847-09
Description: Held with the Pleasant Grove Church, in Platte County, Mo.

Title: Oration Delivered Before the Sons of Temperance, Saint Louis Division
Date: 1847-02-22
Description: On the Anniversary of the Birthday of Washington, February 22, 1847, Together with the Proceedings Observed at the Festival

Title: To the Hon. John Quincy Adams, and the Other Twenty Members of Congress
Date: 1843-10-20
Description: Open letter from a citizen of Texas to Congress concerning the ongoing process of the annexation of Texas to the United States.

Title: Map and View of St. Louis
Date: 1848
Description: Drawn, engraved & printed by J. M. Kershaw, 34 Second St. St. Louis. Kershaw’s plans shows in the border the great building occurring in St. Louis in the 1840’s, truly a frontier metropolis in the making., The St. Louis directory for 1848 : containing the names of the inhabitants, their occupations, places of business, and dwelling houses ... / by J.H. Sloss.

Title: Minutes of the 20th Annual Session of the Hiwassee Association of United Baptists
Description: Convened at Chickamauga Church (by consent of Chattanooga Church) Hamilton Co. Tenn. on Friday before the 4th Saturday in September, 1843.

Title: Address, Delivered in the Chapel of the University of the State of Missouri: On Occasion of the Edifice
Date: 1843-07-04

Title: American Railroad Journal February 12, 1848

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