1. Map of Lockhart River Basin, Great Slave Lake District, Northwest Territories : including the head Creator: Canada. Topographical Survey Published / Created: 1925 Call Number: 743 L79 1925 Container / Volume: BRBL_00395 Image Count: 1 Resource Type: Maps, Atlases & Globes Found in: Beinecke Rare Book and Manuscript Library > Map of Lockhart River Basin, Great Slave Lake District, Northwest Territories : including the head waters of Thelon, Back and Coppermine Rivers / compiled, drawn and printed at the Topographical Survey of Canada.