Action of Aluminum Chloride on Saturated Hydrocarbons. 369 
from this, by treatment with sulphuric acid and distillation 
pure heptane C 7 H ]6 of a constant boiling point of 98°-98.1° was 
•obtained. Aluminum choloride acts on this pure saturated 
hydrocarbon in the same way as on the petroleum ether. 
At ordinary temperatures slowly, and at higher temperatures 
more rapidly, hydrochloric acid and combustible gases are evolved, 
and a product remains in the reaction vessel which is precisely 
like that obtained before, and no more attractive for further 
study since no definite products can be isolated. 
It is hoped that by modifying the conditions some more light 
may be thrown on the course of the reaction, at least so far 
as the gaseous products which are evolved are concerned. The 
gases given off at ordinary temperatures may be determined by 
gasometric methods, and perhaps by letting the reaction go on 
under diminished pressure a sufficient amount of a lower vola¬ 
tile hydrocarbon may be collected to be analyzed. Some pre¬ 
liminary work has already been done in these directions. 
So far these observations may call attention to the practical 
objection to the use of petroleum ether in this reaction, and to 
emphasize the idea that chemical stability is a term which can 
be used in reference to a certain substance or class of substances 
only when the reaction to which these substances are subjected 
is definitely stated. 
Madison , Wis. 
