54 



their relations to the other rocks, which will more fully illustrate the character 

 of this portion of the State. 



The examination of these rocks was continued from Lewis's Bridge on the 

 Trinity, in a northeasterly direction to the base of what is known as Brown's 

 Mountain, a ridge which forms the eastern border of the Weaverville basin. 

 On this ridge there are no vestiges of any other than the primitive series, and 

 trapeau rocks, comporting in character with those spoken of on the Trinity 

 ridge. On the western declivity and a little more than half way down to the 

 level of the basin, the veins were found to be situated in talcose slates, which 

 extend in a broad band from this point to the bottom of the hill ; as usual, the 

 vegetation within the line of its range become much more sparsely distributed 

 than upon either of its flanks where the trap rocks and granites were found to 

 predominate. Following this line for several miles, these talcose rocks were 

 found to be part of an extensive range which composes the major portion of the 

 four prominent peaks situated north of the town of Weaver, which are designa 

 ted as the Weaver Mountains, and which may be known by their peculiarly bar 

 ren aspect, when approaching this town from any point of the compass. This 

 belt extends entirely across the basin, and has been struck, at various points, in 

 sinking shafts and driving tunnels for placer mining. 



Taking a westerly direction along the base of the ridge, and following that 

 line for four or five miles, I observed three dikes of quartz cutting the granite, 

 and one near a small branch which empties into Weaver Creek, which entered 

 the greenstone below the granite. In company with some three or four of the 

 citizens of Weaver, a visit was made to the high ridge west of the west branch 

 of the main creek. In the distance of two miles in reaching the summit of this 

 hill, we crossed as many as five distinct parallel lodes, three of which I subse 

 quently found to contain gold. On the following day, an examination of the 

 southern end of this ridge was made, and a heavy dike of this rock was found 

 occupying the summit, and cropping out at various points on the declivity towards 

 the river. I think that this dike is identical with one which is found on the 

 south-east flank of Brown's Ridge, and it unquestionably cuts entirely through 

 that mountain. 



In all the veins which passed under my observation during my rambles in this 

 section of the State, not one was found to enter any of the rocks of sedimentary 

 origin, but were confined exclusively to the primitive group. On the Tririty River 

 and between that and the Scott, the same features were prevalent in this particular 

 with one exception, which was found at the distance of about two miles from 

 Palmer's Ferry ; here the Argillite slates on the left of the trail were cut through 

 by a single small vein which was traceable for a distance of nearly one mile, and 

 like several veins in the more southern counties of the State ; this lode had a strike 

 nearly due east and west, nearly at right angles to what are known here as the 

 primitive lodes. This is an interesting fact in this county, and serves to show a 

 regularity in those perturbations to which this part of the continent has been sub 

 jected at different periods. Under the article of Mines I shall have occasion to 

 allude to this subject, in connection with the comparative value of the metalliferous 

 character of these lodes, so far as they have been examined and are at present 

 understood in this State. 



From the allusions made to the primitive veins in my report of last year, some 

 idea of their intrinsic value may be gleaned with reference to the prospects which 

 they present for mining operations. 



Finding so great a preponderance of lodes of this character in this district of 

 country, 1 took occasion to collect and examine a consideiable number of these 

 rocks from different veins, and situated miles apart. These collections were 

 from the counties of Shasta, Trinity and the eastern part of Klamath, the 

 aggregate number of which was forty-three, and of this number fourteen were 



