WadtU-r.] OOO [March 



2. 3. 



Carbonic acid 44 .28 



Carbonous oxide 84 .22 



Etliyline series 43 .47 



Ilvdrocren 8.56 7.49 



Marsh-gas 40.83^ / 65.28 26.99^ /59.27 



Ethyl-hydride.. 48.90 > 89.73 < trace 64.56 > 91.55 ■' trace 



11 / 65.28 26.99^ rJ 



I > 89. 73 ] trace 64. 56^91. 55 j 1 



Propyl -hydride. . trace* (24.45 trace' '32.28 



Oxygen 



Nitrogen 



-'o'- 



99.99 100.01 



The hydroc-arlrons of the Marsh-gas series in these three analyses can be 

 counted together with perfect accuracy as 98.50 per cent., 89.73 per cent., 

 or 91.55 per cent, respectivelj^ or we have a choice of two methods of 

 reckoning the individual amounts, with proximate accuracy however 

 only. In these analyses the second metliod of estimation, viz : that di- 

 viding the amount between marsh-gas and propyl-hydridc appears the 

 more probable. 



IV. 0ns from Indiana Co. Pa. 



1. Cherry Tree Well. This gas bubbles through a sjning of fresh water 

 and had to be collected over water. The totally different circumstances of 

 its occurrence will explain in part the differences in composition. The 

 geological horizon is much higher than that of any other gases analysed. 

 It was collected in November, 1875. 



1. 



Carbonic Acid 2.28 



Carbonous oxide 



Ethjiene series 



Hydrogen 22.50 



Marsh-gas 60.27 



Ethyl-hydride 6.80 



Propyl -hydride 



Oxygen 83 



Nitrogen 7.32 



100.00 



A casual examination of these figures with a reference to the approxi- 

 mate geological horizon in each case will show several well-marked pecu- 

 liafities. The Cherry Tree gas wiiich comes from the highest geological 

 horizon, is found to contain 22.50 per cent, of hydrogen and 60.27 percent, 

 of marsh-gas. This would make it the lightest of any of the gases analysed. 



The four from the next lower geological horizon, i. e., the Butler Co., 

 oil-fields, show an advance upon this, and are quite similar, with two 

 somewhat anomalous features showing, however — the 18.12 percent, of 



