In 1711, Englishmen interested in news from North America were entertained by a representation of the efficiency displayed by Canadian beavers in dam building, engraved in the border of a “New and Exact Map of the Dominions of the King of Great Britain” on this continent. The map is in an atlas of Herman Moll, a prominent British cartographer of the early eighteenth century. The atlas is a recent acquisition of the Society. This particular map is in great demand by public utility companies, as the first historical reference to the production of water power in America, and copies of it, when they can be found, bring from two to three hundred dollars.