264 PETROLEUM 



and they used it for a variety of purposes, but it is only in 

 modern days that its use has become so extensive. 1 



The depth at which oil occurs varies ; in Ontario the wells 

 are about 400 feet deep. Sometimes it comes up of its own 

 accord, but more often it has to be pumped up. The oil thus 

 obtained is crude oil, and before it can be used it has to be 

 refined. 



A large iron cylinder, called a still, is filled with oil and 

 then heated. The vapour from the boiling oil passes through 

 a long pipe which is kept immersed in cold water. In this 

 pipe the vapour condenses into naphtha and refined oils of 

 various kinds. These are further purified, and at last petroleum 

 such as we know it is obtained. In the still there remains 

 a residuum, which on being distilled yields oil and vaseline. 

 Altogether during the process of refining about 200 useful 

 by-products are obtained. 



Petrol, such as is used in all kinds of motors, is a volatile 

 spirit obtained from petroleum by distillation, and the amount 

 required for this purpose alone is enormous and is continually 

 increasing. In addition to this, experiments are constantly 

 being made with oil as fuel instead of coal, and as a result 

 of these experiments we shall in the future most certainly 

 require larger and larger supplies of petroleum. 



Far and away the largest producer at present is the United 

 States, and next in order comes Russia, who possesses impor- 

 tant wells at Baku on the Caspian Sea. Roumania and 

 Galicia, too, have large oilfields, though small compared 

 with those of the United States. 



In our own empire, unfortunately, our supplies are altogether 

 insufficient for our needs, but there are many promising 

 fields for experiments and enterprise, and there is but 



1 ' Neere unto this Town (Baku), is a very strange and wonderfull Foun- 

 taine under ground, out of which there springeth and issueth a marvellous 

 quantitie of blacke Oyle, which serveth all the parts of Persia to burne in 

 their houses ; and they usually carrie it all over the Country, upon Kine 

 and Asses, whereof you shall oftentimes meete three or foure hundred in 

 company.' John Cartwright, 1603 (Purchas his Pilgrimes). 



