228 RESEARCHES UPON THE CHEMICAL PROPERTIES OF GASES. 



dant as to seriously interfere with gas development, l^ote by F. C. P.) Such 

 alkaline waters are not known in archsean rocks, and are not, therefore, likely to be 

 derived from greater depths than the rocks in which they are found. 



Probably no cases can be cited where fatty tissues alone of buried animals have 

 yielded oil or gas. The presence of strongly saline water is apparently needed. 



Great differences occur in the chemical character of petroleum. Caucasian oils 

 are mainly composed of olefines or substances related to the olefine group. The 

 German oils are mixtures of paraffins and olefines, while the American are chiefly 

 paraffins. Such differences may be attributed to the character of the rock in which 

 the distillation has occurred. Sandstones would probably prove without action ; 

 while limestones, by reason of their basic character, would tend to strongly influence 

 the products. 



Such are some of the arguments of Ochsenius in favor of Engler's hypothesis. 



If this view is accepted, it follows that the generation of petroleum and gas 

 must be considered as a finished process, so far as all existing productive gas and 

 oil I'egions are concerned. 



Engler has analyzed the gas evolved when (1) menhaden oil and (2) when oleic 

 acid are distilled under atmospheric pressure and under a pressure of 25 atmospheres. 



MENHADEN OIL. OLEIC ACID. 



1 ATMOS. 25 ATMOS. 1 ATMOS. 35 ATMOS. 



Metliane 25.2 38.3 9.3 4.36 



Olefines 11.4 7.8 12.5 2.9 



Carbon dioxide 26.7 17.4 37.2 26.0 



Carbon monoxide 34.9 34.5 38.6 25.5 



Incombustible residue 1.8 2.0 2.4 2.0 



(Ser., 1889, p. 593). 



The liquid distillates produced at the same time that these gases were evolved 

 were rich in the normal paraffins and their isomers. 



100 parts of menhaden oil yielded 8.9 parts of gas and 63 parts of liquid oils. 



A strong argument in support of the Engler hypothesis is found in the fact that 

 by distillation of fish oils, besides methane, several of the lov/er paraffins are pro- 

 duced in large quantity. Hydrocarbons of the paraffin series are not obtainable in 

 such proportions by the distillation at high temperatures of other organic material 

 under ordinary conditions. 



It should be noted as a fact of much interest as regards the results of Engler's 

 researches, that in the distillation at higher pressures the proportion of olefines con- 

 tained in the gases evolved is considerably less. This is also true of carbon monox- 

 ide when oleic acid was distilled. It is to be regretted that Engler's experiments 



