RESEARCHES UPOIST THE CHEMICAL PROPERTIES OF GASES. 219 



the use of cuprous chloride for the absorption and recognition of carbon monoxide 

 cannot be implicitly depended on. Still, the direct tests above named lead me to the 

 conclusion that no carbon monoxide occurs in our natural gas. 



PARAFFiisrs. 



That the lower paraffins occur in natural gas needs no proof. Methane is the 

 chief constituent. Small quantities of higher paraffins are usually present. 



SULPHUR COMPOUNDS. 



Pennsylvania natural gas does not contain recognizable quantities of either COS, 

 CH3SH or (CH3)2S. Towards the western boundary of the State it is possible that 

 minute traces of sulphuretted hydrogen occur. The quantities of all such com- 

 pounds are far too small to allow of their being easily identified, even in the case of 

 large volumes of gas. The extreme delicacy of the reaction of meth}^ mercaptan 

 towards palladium chloride would render it possible to detect exceedingly minute 

 quantities of this compound should it occur. 



I have not had an opportunity to test the gas from the Westei'n Ohio territory, 

 which is said to contain sulphur compounds in considerable quantity. 



NITROGEN. 



N^atural gas, dried by calcium chloride and phosphorus pentoxide, was passed 

 over strongly heated magnesium powder. The magnesium was partly converted 

 into a nitride, easily recognized by its reaction towards moisture, yielding ammonia 

 in considerable amount. 



Repeated trials have been made of natural gas in the following way: 

 A measured volume of gas was passed over ignited oxide of copper contained 

 in a porcelain tube, the entire apparatus having been previously filled with pure car- 

 bon dioxide, w^hich was caused to flow in a continuous stream for several hours in 

 order to expel all traces of air. The escaping gas was collected in a eudiometer over 

 mercury and the carbon dioxide absorbed by soda. There was left invariably a 

 residue of gas unabsorbed by the soda and having no action upon palladium chloride 

 solution. This residual gas was evidently nitrogen (see Table of Analyses). In 

 the gas found in an artesian boring at Middlesborough, England, nitrogen was found 

 in large proportion (see Table of Analyses). 



OXYGEN. 



By the use of pyrogallol and soda, and by the oxidation of manganous hj^drate 

 in water, I have frequently been able to detect traces of oxygen, although on other 



