240 ASSINNIBOINE AND SASKATCHEWAN EXPEDITION. 



Its most easterly point being the lake and swamps 

 from which the Savanne Eiver takes its rise, in lon- 

 gitude 90° 14', latitude 48° 53', and the most westerly 

 limit from which it draws contributions is probably the 

 Glacier, near Howse Pass, in longitude 117° 35', latitude 

 51° 52'.* 



The southern extension of its boundary is at Lake 

 Traverse in Dakotah territory, longitude 96° 45', latitude 

 45° 58'. f It stretches north as far as Frog Portage, 

 longitude 103° 30', latitude 55° 26'.$ 



This basin consequently extends over twenty-eight 

 degrees of longitude and ten degrees of latitude. 



The elevation of its eastern boundary is 1485 feet 

 above the ocean, and the height of land near the sources . 

 of the tributary, which rises farthest to the west, is 6347 

 feet above the same level. § 



Its northern boundary is separated from the valley of 

 the Missinnippi by a low portage, over which waters flow 

 during floods ||; while towards the south Lake Traverse, 

 which also sends water into the Mississippi during spring 

 freshets, is only 820 feet above the sea.^j" 



The outlet of Lake Winnipeg is through the contracted 

 and rocky channel of Nelson Eiver, which flows into 

 Hudson's Bay. 



The mean breadth of this great inland basin is about 

 380 English miles, and its mean length 920 miles, hence 

 its area is approximately 360,000 square miles. Its shape 

 assimilates to that of a truncated section of a circle, lying 



* See Captain Palliser's Map in the Blue Book, 1860. 

 t Military Map of Nebraska and Dakotah, by Lieutenant Gr. K. Warren, 

 U.S. Top. Eng. 



\ Sir John Richardson, Arctic Searching Expedition. 

 § Dr. Hector, Blue Book. Captain Palliser's Explorations. 

 || Sir John Richardson, 

 ij Major Long. 



