RESEARCHES ON THE VOLATILE HYDROCARBONS. 175 
Or tHe Catcutatep Borine-points oF Hyprocarpons BY GERHARDT’s THEORY. 
We come finally to test the law of Gerhardt, above mentioned. Inasmuch as this 
law was specially designed to apply exclusively to the hydrocarbons, — upon the ob- 
served boiling-points of some of which it was indeed founded, — we should naturally 
expect to find this more in accordance with facts than either the hypothesis of Schro- 
der or that of Léwig, both of which were claimed to be of more general application, 
and were framed more especially with reference to other classes of substances. The 
facts presented in the following tables will show, however, that this is far from being 
the case ; and that the theory of Gerhardt, as well as those of Schréder and Lowig, so 
far as these relate to the hydrocarbons, was by no means legitimately drawn from 
nature, but is altogether artificial. 
1. Hydrocarbons from Pennsylvania Petroleum. 
lst SERIEs. 
5 
A Calculated Boiling- | Difference between 
oe ant | PE eee a 
C, Hy. 020 (?) —8.0 a 
Cio Hes 30.2 12.5 17.5 
Cy Hy 61.3 33.0 28.3 
Cy, Hyg 90.4 53.5 36.9 
Cre Hyg 119.5 74.0 45.5 
Cis Hoy 150.8 94.5 56.8 
2p SERIES.* 
F Calculated Boiling- | Difference between 
Formula. (2) ee eames point by Gerhardt’ Calonated aul Deter. 
° ° i ° 
Cy Hay 8-9 —8 16.5 
Cy Hy 87.0 12.5 24.5 
Cy, Hy 68.5 33.0 35.5 
Cy, is 98.1 53.5 44.6 
Cie Hu 127.6 74.0 53.6 
3p SERIES. 
; Calculated Boiling- | Difference between 
Formula. rel ae od point oa pee ee ae 
° ° ° 
Cy Ha 174.9 1380.0 44.9 
Cy He 195.8 150.5 45.3 
Cy Hay 216.2 171.0 45.2 
* See foot-note on page 167. 
