[camsell] great canon OF FRASER RIVER 49 



section, 30 miles in length and extending from Lytton to Anderson 

 river, is characterized by a relatively broad valley with timbered 

 slopes having in its lower parts terraces of gravel and only rarely 

 showing outcrops of the solid rock. The middle section, having a 

 length of 24 miles and extending from Anderson river to Yale, is the 

 gorge. It is the most constricted part of the mountain portion, and in 

 it the river flows with a grade of about 8 feet to the mile between high 

 rocky slopes that are usually so steep that gravel and other loose 

 material have little place for lodgement. The lower slopes of this 

 section are flanked by rock benches rather than by drift terraces, and 

 the stream has cut so deeply into the solid rocks that to the early 

 placer miners this section was commonly known as the. "sluice box." 

 The lower section is that extending from Yale to Agassiz a distance of 

 32 miles. This section has characteristics somewhat similar to the 

 section above the gorge. In its lower part, however, the grade of the 

 stream lessens and its bed is occupied by islands of gravel. The 

 valley also quickly widens and the bordering mountains depart 

 farther from each other to give place to the delta. 



Lytton to Anderson River 



In the section Lytton to Anderson river the Fraser river occupies a 

 broadly flaring valley, terraced on its lower slopes by benches of gravel, 

 and rising gently on the eastern side to heights of 5,000 feet or more 

 and on the other side to slightly greater elevations. The course of the 

 valley is fairly direct, and the stream flows down a grade of about 4 feet 

 to the mile with a strong steady current cutting here and there into the 

 lower benches and exposing sections of gravel 100 feet or so in height, 

 but only occasionally uncovering the solid rocks beneath. 



The trend of this section of the valley coincides closely with the 

 strike of the rocks, and the direction taken by the stream has no doubt 

 been greatly influenced thereby. For a great part of the distance 

 between Lytton and Anderson river the valley has been excavated 

 partly in Cretaceous sediments and partly along the contact between 

 Cretaceous and older sediments; and the location of the valley in that 

 position may have been determined by the softness of the Cretaceous 

 rocks or by the line of weakness at the junction of the Cretaceous and 

 older rocks. 



No tributaries of consequence join the Fraser in this section of 

 its course, the most important being the Nahatlatch or Salmon river 

 and Anderson river. The other feeders are short streams of small 

 volume rising at no great distance in the adjacent mountains and 



Sec. IV, Sig. 4 



