36 PROCEEDINGS OF THE CANADIAN INSTITUTE. 



most part, complicated apparatus is not required. A derrick for 

 lifting the mineral and debris, and a pump to carry off the accumu- 

 lated water, seem to constitute, in most places, the entire plant. 



The process consists in drilling holes of various lengths — one man 

 holding the drill, which may be of inch and a-quarter steel, and 

 another, or two, hammering. In places where there is not sufficient 

 room for the striker, a long drill is often attached to a spring-pole. 

 The method of working in this case is obvious. The holes are charged 

 with gunpowder or dynamite, and well tamped with sand and broken 

 rock matter, and the adjacent ai'ea is loaded with heavy logs to pre- 

 vent too much scattering of the phosphate. The fuse being left of 

 sufficient length to allow the men to retire in safety, the charge is 

 fired. After the explosion the lumps of pure phosphate are placed 

 by themselves, and those containing intermixed rock matter are 

 removed to the dressers' tables, whei'e, with small hammers specially 

 made for the purpose, the gangue is separated as far as possible ; but 

 the phosphate being much softer than the intermixed matter, this can 

 only be approximately done. Hitherto a phosphate containing 

 70%Ca3(POi)2 or over has been required, but probably in the future 

 much of the stuff now in the " dump " will be used. 



The gangue consists chiefly of quartz, feldspar, phlogopite (magne- 

 sian mica), pyroxene and calcite, and these, therefore, constitute the 

 principal impurities in the commercial article. The predominance 

 of calcite not only lowers the percentage of calcic phosphate, but de- 

 composes much of the acid when the mineral is being converted into 

 "superphosphate." The other impurities are insoluble in sulphuric 

 acid, and consequently only lower the percentage of apatite present. 



In this district (Templeton), if the mines are near navigable waters, 

 the mineral is brought down in scows as far as possible, from whence 

 it is teamed to the Ottawa River, where it is re-loaded on barges, or 

 on the cars of the Canadian Pacific Railway for Montreal. It is 

 shipped here as ballast principally, and exported to England, where 

 it is treated with sulphuric acid, converting it into an acid phos- 

 phate of calcium, or " superphosphate," containing more or less 

 sulphate of calcium, and sold either per se, or mixed with blood and 

 other refuse for agricultural purposes. The action of sulphuric acid 

 at a moderate temperature upon apatite may be thus depicted : 



Ca3(P04), + 2H.S0, = CaH,(P0,)2 + 2CaS0,. 



