1908.] MABERY—THE COMPOSITION OF PETROLEUM. 45 
last year, indicates that the so-called asphaltic hydrocarbons forma 
part of this petroleum with very high boiling points. This places 
Pennsylvania petroleum in the same category with the heavier 
petroleum from such fields as California and Texas, the chief dif- 
ferences being the predominating series C,H,,,, in Pennsylvania 
oil and the series poorer in hydrogen in the heavier products. As 
explained above, the large proportion of the paraffine hydrocarbons 
in the heavy portions of Pennsylvania oil apparently render the 
lubricating distillates more stable. Just what effect it has on the 
lubricating qualities, so far as I know, has not been completely 
determined. Some experiments on the very heavy lubricants from 
Beaumont oil have demonstrated very superior lubricating qualities. 
Ou10 TRENTON LIMESTONE PETROLEUM. 
Since the first discovery of this petroleum, there has been great 
uncertainty concerning its composition. In the preparation of 
commercial products, the refiner discovered essential differences 
between it and Pennsylvania oil which were fully understood with 
reference to its refining qualities. The first serious obstacle was 
the large amount of sulphur compounds that must be removed for 
the production of acceptable burning oil. Innumerable patents 
were issued for processes which included distillation over quartz, 
precipitation with mercuric chloride, oxidation with potassium per- 
manganate, and numerous other impracticable ideas that had been 
tried only on paper. The ordinary refiner distils over scrap iron 
and refines with alkaline lead oxide. From much the greater part 
of refining oil sulphur is removed by distilling over heated copper 
oxide and recovery of the oxide, a process that is said to have 
originated in Canada, but is known as the Frasch process. Prob- 
ably fifty tons of sulphur daily is a conservative estimate of the 
amount extracted from Ohio oil and burned off into the atmos- 
phere. It is claimed for this process that it is capable of removing 
the sulphur to 0.02 per cent., which is probably correct. Excel- 
lent burning oils are made from Ohio petroleum. 
The composition of Ohio petroleum, so far as the portions 
readily distilled are concerned, has only been arrived at within the 
last few months. Several years ago an examination of the sulphur 
petroleums, as Ohio and Canadian petroleum was then designated, 
showed that the series C,H,, ,, formed the portions of Ohio crude 
