54 



which at times form small partings, affecting to some extent the value 

 of the material. The containing rock shows the presence of numerous 

 faults, as in other mineral localities, which throw the veins from side 

 to side, and at times completely cut off the entire working face of the 

 mine. The sides of the fissure are in such cases extensively slicken- 

 sided, and often have streaks of coarse, woody-fibred or imperfect asbes- 

 tus along the planes of fracture. The growing importance of this indus- 

 try may be seen from the fact that the output of the mineral has 

 increased from 50 tons in 1878 to over 4,500 tons in 1888, while the 

 demand and value are rapidly improving. 



Apparently confined almost exclusively to the same group of Cam- 

 brian rocks are the gold deposits of Eastern Quebec. First discovered 

 in 1835 on the Chaudiere River and its tributaries, this industry for a 

 long time almost entirely appertained to this locality, though a second 

 and possibly quite as important gold field has been worked to some 

 extent for the last fifteen or twenty years in the extreme south-easterly 

 part of the Province, in the Township of Ditton. The rocks which 

 constitute not only those which we now regard as the original source 

 of the gold of this section, but the overlying Cambro-Silurian slates 

 and limestones as well, were for many years regarded as of Upper 

 Silurian age, although their resemblance to the Cambrian gold-bearing 

 series of Nova Scotia had been pointed out long since by Sir "Wm. 

 Logan, Dr. Selwyn, Dr. Hunt and others; and the only reason apparent 

 why these rocks were allowed for so many years to remain in the 

 Silurian system was that the great importance of the geological prob- 

 lems pertaining to the structure of the metamorphic portion withdrew 

 attention almost entirely from this area. 



The Silurian age of these sediments was first of all inferred by the 

 officers of the Geological Survey from their supposed resemblance to the 

 rocks of that system which had been studied in Gasp^, and it was sup- 

 posed that these formed the western prolongation of the Gasp6 limestone 

 :series. The presence, also, of areas of fossiliferous Silurian and Devonian 

 -strata at various points, which were in places so intimately associated 

 with the rocks of the great eastern basin as at first sight to appear to 

 form an integral portion of the series, supported this fii'st view as to 

 heir apparent horizon. In the subsequent detailed study of the country 



