78 Proceedings of the Royal Society of Edinburgh. [Sess. 
In Trinidad asphalt, which, as has been seen, consists of highly in- 
spissated petroleum mixed with water and inorganic matter, the average 
percentage of nitrogen in the bitumen is "81 per cent. (Clifford Richardson). 
In the less inspissated bitumen from Bermudez Lake, Venezuela, it is 
*75 per cent. 
But if the “ organic matter not bitumen ” in Trinidad asphalt be ex- 
amined, the nitrogen percentage is found to be 2’05 per cent., while the 
oxygen is as much as 27 ‘29 per cent., indicating how thoroughly the 
material has been inspissated. In the malthenes, the least oxidised and 
inspissated portion of the asphalt, the nitrogen percentage is ’6, and in the 
saturated hydrocarbons in the malthenes the percentage is only ’07. Set 
out more fully, we have the following table : — 
Percentages of Nitrogen in Organic Matter in Trinidad Asphalt. 
Saturated 
Hydrocarbons 
in Malthenes. 
Total 
Malthenes. 
Total 
Bitumen. 
Unsaturated 
Hydrocarbons 
in Malthenes. 
Asphaltenes. 
Organic Matter 
Non-bituminous. 
•07 
•6 
•81 
•92 
1*2 
2-05 
This is direct proof that the nitrogen compounds become concentrated in 
the inspissated products, part of which, as we have seen, become adsorbed 
in the argillaceous mineral matter and insoluble in carbon disulphide. 
We should expect, therefore, in a natural bitumen such as albertite, 
which contains some 90 per cent, of matter insoluble in carbon-disulphide, 
that the percentage of nitrogen will be high. It is 1*75; while in gilsonite 
it is *79, and in Egyptian glance pitch, a very pure bitumen containing 
only 2 per cent, of organic matter and T per cent, of mineral matter, the 
percentage of nitrogen is only T9. 
Evidence of this nature could be given at great length, but perhaps the 
above is sufficient. 
We should expect also that the shales associated with albertite should 
give a high percentage of nitrogen and give evidence of oxidation of the 
kerogen content. Unfortunately, I have been unable to find analyses of 
these shales giving the nitrogen percentage ; but the fact that throughout 
a test lasting 'seventeen days, made by the Pumpherston Oil Company, the 
shales from Albert County gave an average of 7 6 ’94 lbs. of ammonium 
sulphate per ton is sufficient proof that they are richer than the average 
Scottish shale in nitrogen. Albertite yields 65 lbs. per ton; the average 
yield of ammonium sulphate is about 35 to 40 lbs. per ton for Scottish 
shales. 
