EXAMINATION OF A NAPHTHA FROM LIME-SOAP. 201 
we have just now alluded to; this compound, of P.& C.,is in any event uncon- 
formable with either of the series of hydrides which are known to exist in petroleum. 
It is of course always possible that cases may occur where, from insufficient quanti- 
ties of material, it will be impracticable to continue the process of distillation until_a 
constant boiling point has been reached; indeed, this inability will in most instances oc- 
cur, in due course, at either end of every long series of fractions which have been ob- 
tained as in the present case from a complex mixture of substances; we would insist 
only upon the fact that doubts as to the definite character of any small heap will be 
far less likely to arise when the process of distillation has been carefully and methodi- 
cally conducted from beginning to end. 
With regard to the bodies which we have obtained at or near 140° and 170°, it is no 
doubt still conceivable that they are not really impure xylole and isocumole, as we sup- 
pose, but new compounds, and the observations of Tollens and Fittig,* upon mixed 
radicals of the ethyl and phenyl] series, would seem to strengthen this thought; but in 
our opinion the weight of evidence is decidedly in favor of the view which places these 
140° and 170° compounds in the benzole series. As we understand it, our own experi- 
ence indicates that the members of the benzole series are peculiarly liable to retain a 
certain portion of the more highly hydrogenized hydro-carbons so forcibly that these 
cannot be readily separated by fractional condensation. 
Margarylene = Co, He. At 193°-196° was a heap of about 650 ¢ ¢ Its sum- 
mit was well defined at 194°-195°, from which point it fell away gradually on either 
hand through several degrees. It was treated with diluted sulphuric acid in the usual 
way, the first portion of acid becoming quite dark, and the second, third, and fourth 
portions each less dark than the preceding, The hydro-carbon itself began to be 
colored on the fourth addition of acid. 
In an ordinary retort upon metallic sodium it boiled at 195.4° (corrected). 
On combustion, an unweighed portion of it gave 0.2721 grm. water, and 0.6478 grm. 
carbonic acid. Or, 
Found. Theory. = 
Carbon 85.40 Cog 85.71 
Hydrogen 14.60 Hye 14.29 
100.00 100.00 
A determination of the density of its vapor gave the following result : —. 
Temperature of balance, . ‘ - A ‘ 2 ‘ . . F , - 24.5 ° 
* Annalen der Chemie und Pharmacie, 1864, CX XIX. 369 and CXXXI. 303. 
VOL. IX. 30 
