NATURAL AREAS AND REGIONS 



127 



Mackenzie, joins it just south of latitude 

 65°. Below its mouth, on the north side 

 of the Mackenzie, is Bear Rock, 1400 

 ft. in height. 



Below here the Mackenzie resumes 

 its general northwesterly course. Wol- 

 verene Rock, 100 mi. below Bear Rock, 

 is formed, like that eminence, by an 

 uplight of the Devonian limestone, 

 and is about 1000 ft. in height. Twenty- 

 five miles below here a rocky ridge 

 crosses the river, forming the Sans 

 Sault Rapid. The next important fea- 

 ture in the valley of the Mackenzie is 

 the defile called the "Ramparts." 

 Here the river contracts from a width 

 of 2 mi. to about 500 yds., and flows for 

 about 7 mi. between precipitous lime- 

 stone cliffs, which in places rise to a 

 height of 250 ft. 



Below Sans Sault Rapid the Mac- 

 kenzie recedes from the mountains, 

 and they are not again visible until the 

 delta is reached. Hareskin River enters 

 the Mackenzie from the east a short 

 distance north of the Ramparts. It 

 drains a large extent of rocky wooded 

 country between Great Bear Lake and 

 the Mackenzie. For a long distance 

 below here the Mackenzie maintains a 

 general northwesterly course. In about 

 latitude 67° 40' it turns rather abruptly 

 at right angles, and for about 50 mi. 

 follows a course considerably south of 

 west. It is here bordered, especially 

 on the north, by high clay banks, 

 through which several good-sized 

 streams cut their way. The river then 

 turns northward again and maintains a 

 northwesterly direction to the delta. 

 The defile called the "Narrows" or 

 "Lower Ramparts" is encountered near 

 67° 40', and at its lower end Arctic Red 

 River, from the south, discharges its 

 muddy waters. As far as known the 

 country bordering this part of the 

 Mackenzie on both sides is rolling, well 

 watered, and fairly well wooded. A 

 few miles below Arctic Red River the 

 high banks of the Mackenzie gradually 

 become lower and the river spreads 

 out into the delta. 



The Mackenzie Delta occupies a 



triangular area nearly 100 mi. in length 

 and 50 mi. broad at its widest part. 

 To the westward of the delta lies a 

 range of high hills, the northern ex- 

 tremity of the Rocky Mountains. They 

 rise to a height of from 1200 to 1500 ft., 

 and their lower slopes only are wooded. 

 The Caribou Mountains, apparently a 

 continuation of the ridge which crosses 

 the Mackenzie at the Lower Ramparts, 

 lie to the eastward of the delta. They 

 rise to a height of 700 to 800 ft. and are 

 less rugged than the mountains west 

 of the delta. 



Climatology: The climate of the Mac- 

 kenzie Valley is fairly indicated by the 

 tables of temperature which follow. 

 They were taken in 1900, which seems 

 to have been a year of about average 

 conditions. 



Summaries of temperatures taken at Fort 



Simpson, Mackenzie, during 



the year 1900 



January . . 

 Februarv . . 



March 



April 



May 



June 



July 



August — 

 September 

 October — 

 November 

 December. 



Year 



■< 



» 



a 



o 



s 



-24 8 

 -21 4 

 -2 3 



29 5 

 43 9 

 57 3 

 57 6 

 54 5 

 45.7 

 24.1 

 -1.7 

 -13.7 



20.7 



The temperatures of the extreme 

 upper Mackenzie are undoubtedly 

 slightly lower than those recorded for 

 Fort Simpson, but comparable data are 

 not at hand. 



Comparable figures for points in the 

 valley of the lower Mackenzie and for 

 Herschel Island show that the winter 

 climate of the upper and lower Macken- 

 zie varies but slightly, while the summer 

 climate is considerably cooler to the 

 northward. 



As has been stated, the warm winds 



