604 THE OIL-FIELDS OF EASTERN CANADA. — ELLS. 



proportionally wide range, extending from 0.771 to 1.020. As 

 a rule, the lighter oils yield a larger percentage of kerosene than 

 the heavier grades. Comparing the oils of western Ontario 

 with those from the celebrated wells fonnd in the United States 

 iit is found that the Canadian product has a somewhat greater 

 specific gravity, while tests made on the oils taken from the 

 wells in Graspe during the borings some years ago, gave some- 

 times a still higher specific gravity. The oils of western Ontario 

 have also a more offensive odor than manv of those to the south, 

 due presumably to the presence of sulphur. 



In colour, native oils range from a light yellow to a black or 

 brownish-black, and often with shades of green. In regard to 

 density this is measured by what is known as the Baume scale, 

 in which the lower the grade on Baume the higher the specific 

 gravity of the oil ; thus, 10 degrees Baume is equivalent to 

 specific gravity 1.000, while 90 Baume is the equivalent of an 

 oil with specific gravity 0.6363. 



Turning now to the consideration of the co'nditions under 

 which petroleum in economic quantity is usually obtained, it 

 will be observed that the general arrangement of the rock 

 formation is a very important factor, whether the locality be 

 ■underlaid by rocks of the older or the 'newer horizons ; and this 

 feature is sometimes lost sight of in search for new oil-fields. 

 Tor not only must the rocks in which the oil is supposed to 

 ■occur lie in a nearly horizontal attitude, or in the form of 

 low swelling anticlines but the oil itself must be kept in by an 

 impei-vious covering of shale or some other rock. If in the case 

 of a rock series, which is supposed to carry oil in greater or less 

 amount, this covering is broken or faulted or the rocks, as a 

 whole, are more or less tilted and disturbed, it is probable that 

 the cementing cover is quite unequal to holding down the 

 underlying oil, which will therefore in some way tend to find 

 a!n outlet to the surface, and will have been lost in ages long 

 since past. It is, therefore, evidently unwise, to say the least, 



