Map of the Northwest North American continent at the time of Lewis and Clark's Expedition. The map is from Patrick Gass's 1810 account of the expedition "Voyage des capitaines Lewis et Clarke : depuis l'embouchure du Missouri, jusqu'à l'entrée de la Colombia dans l'Océan Pacifique ; fait dans les années 1804, 1805 et 1806, par ordre du gouvernement des États-Unis."
A work of geo-politics by De l’Isle and presented by his Amsterdam publishers — showing the French lands in the context of a still relatively unexplored and unverified northwestern continent, and compared to the known world ca. 1720.
Popple was an associate of astronomer and mathematician, Edmund Halley, and the advertisement in the inset cartouche for this map stresses that friendship in an endorsement for the map’s accuracy, depicting fields, forts, towns, rivers, bogs, forests, all from St. Louis’s future area, well mapped, showing the Missouri River in detailed positioning, also the Meramec River, Cahokia and Kaskaskia to the projected source of the Mississippi, making the most detailed English attempt to map the reaches of the upper Mississippi to its time.