86 E. B. Andrews on the Geological Reiations of Rock Oil. 
of their bituminous properties. The cannel coal although some- 
what earthy, yields from forty to sixty gallons of oil to the ton. 
The other theory, that the oil was produced at the time of the 
original bituminization of the vegetable or animal matter, has 
many difficulties in its way. If the oil were formed with the bitu- 
men of the coal, we should expect that wherever there is bitumin- 
ous’ coal there would be corresponding quantities of oil. This is 
not so in fact, for, as will be seen presently, there is no oil except 
in fissures in the rocks overlying the bituminous strata, and these 
fissures can be shown to have been made since the coal strata 
became bituminized. Again, upon this theory it will be difficult 
to explain the large quantities of inflammable gas always accom- 
anying the oil. If it is generated exclusively from the oil, 
then we should expect to find the quantity of oil least where the 
gas springs have for ages been the most active, but at such places 
the oil, instead of being wasted, is the most abundant. 
That the oil is accumulated in fissures in the rocks and that 
these fissures are more or less vertical there is abundant proof. 
The oil in the same neighborhood is found at very different 
depths. It is very seldom that two adjoining wells strike the oil 
at the same distance below the surface. The accompanying dia- 
gram shows the relative depths of oil wells on Burning Spring 
Run in Wirt Co., Va. It is evident that in this case the oil is not 
1. 
1 2 era 5 Ore 8 
Fig. 1 shows the relative depths of the large wells in Burning Spring Run. 
contained in anything like a horizontal reservoir. The famous 
Lewellyn well marked No. 2, struck an oil fissure at one hundred 
feet, while the Athens company’s well marked 8, struck a large 
vein at two hundred feet. The oil in the first is said to stand 
at 41°, (Beaumé,) while that of the latter stands at 33°. On Duck 
Creek, Washington Co., Ohio, wells very near each other show 
a difference of ten degrees (Beaumé) in specific gravity. — 
