18 j 



GEOLOGICAL SURVEY OF CANADA. 



Varying char- 

 acter of the 

 rivers. 



Navigation. 



watershed to Lake Huron ; the eastern or Abitibbi branch flows out of 

 Lake Abitibbi, a short distance from Lake Temiscamingue on the 

 Ottawa Eiver. 



All the rivers flowing into the west side of James' Bay present the 

 same physical characters ; on their headwaters and upper parts, while 

 flowing over Archean rocks, they alternate between long lake-like 

 expansions with little current, and short contracted portions accom- 

 panied by heavy rapids and falls, thus affording good stretches of 

 navigable water with portages between. On their lower courses, for a 

 distance of one hundred and fifty to two hundred miles from their 

 mouths, where they pass over the flat Devonian and Silurian limestones, 

 the fall is uniform, and consequently the character changes, so that in 

 ordinary low water during the summer and early autumn, owing to 

 this uniformity of fall and to the rivers having too great a breadth for 

 the amount of water discharged at this period, they present an almost 

 unbroken succession of small shallow rapids, full of boulder and gravel 

 bars, and only navigable for canoes of light draft. . 



For three or four weeks after the ice leaves the rivers, during the 

 spring freshet, and again after the autumn rains, the higher water 

 flattens out these numerous rapids and covers all obstructions, so that 

 navigation with large boats, and even small steamers, is then possible; 

 but at these times the current has a uniform rate of between five and 

 six miles an hour, and therefore comparatively powerful steamers 

 would be required to ascend the streams, the boats at present used bein«- 

 tracked up by men along the banks. 



Near the head of Eupert Bay the Little Nottaway Eiver enters. It 

 is a small stream draining the country to the south between Hannah 

 Bay and Nottaway Eiver. This was called formerly Onengham 

 Creek and was used as a winter harbour by the first voyageurs to the 

 bay in the Company's service. 



The mouth of the NottaWay Eiver is directly at the head of Eupert 

 Bay. This is a large river, one of whose branches rises in Lake 

 Chibougamoo, a short distance to the westward of LakeMistassini, and 

 to the northward of the headwaters of the Ashouapmouchouan Eiver, 

 which empties into the Saguenay by way of Lake St. John ; the other 

 branch comes from a more southerly direction and rises near the 

 heads of the Gatineau and St. Maurice rivers. In its lower parts the 

 Nottaway Eiver is so rough and rapid that instead of using it as a 

 route to Waswanippi, a post on its upper waters, the Hudson Bay 

 Company's canoes ascend the Eupert Eiver, itself a very bad route, for 

 one hundred miles to Lake Nemiscow, and thence pass by a portage 

 route through small lakes and streams to the Nottawav. 



