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.
