368 Canadian Record of Science. 



of minerals or materials of eruptive origin, the important 

 part which volcanic rocks play in the portion of the Cordil- 

 lera belt which is included in British Columbia, and the 

 great amount of alteration which some of these have 

 suffered, go far to explain the abundance of jade imple- 

 ments among the natives of the same region, while the 

 great continuity of identical geological conditions in a 

 direction parallel to the coast, may well go hand in hand 

 with the abundance of jade implements actually occurring 

 along the same line. In the province of British Columbia, 

 we find volcanic rocks forming considerable portions of 

 at least five distinct geological systems, viz., the Cambrian, 

 Carboniferous, Triassic, Cretaceous and Miocene. Of these, 

 the first and last may be excluded from consideration ; the 

 Cambrian as not yet recognised in the districts in which 

 jade tools are found, the Miocene as being in general, 

 if not in all cases, in a nearly unaltered state. It is among 

 the highly altered and recomposed volcanic rocks of the 

 Carboniferous and Triassic, that silicates of the jade class 

 might be expected to occur ; and I feel little doubt that 

 when these rocks are carefully investigated, they will be 

 found to be the sources of the jade, though the Indians of 

 the region have usually, if not invariably, obtained their 

 supply from loose fragments and boulders. 



The peculiar adaptability of jade to the manufacture 

 of implements is shown by the mode of working it which 

 has been in use by the natives, which is clearly indicated 

 by specimens from different parts of the whole region 

 from the Fraser Eiver to the Arctic Sea. A suitable 

 fragment having been discovered, it has evidently been 

 carefully sawn up into pieces of the required shape and 

 size, the sawing having been effected either by means of 

 a thong or a thin piece of wood, in conjunction with 

 sharp sand. This rude method of dividing the stone must 

 have been very laborious, and produced a widely gaping 

 cut .before any great depth was obtained. From the frag- 

 ment of a boulder obtained at Lytton (Fig. 2) flat pieces 

 intended for adzes have been sawn off, the cuts having 

 been carried in from the surface, on each side, till it be- 

 came possible at length to break the central rib by which 



