346 Scientific Intelligence. 
fire spontaneously in the air. The formula of this body was found to be 
1,(C,H,),, with which the vapor-density 2°80 closely agrees, the theo- 
retical number being 2°56. But the vapor-density was found to increase 
—Chemical News, No. 271, p. 61. 
5. On the density of the vapor of salammoniac.—H. Sr. Crarre Dz- 
VILLE has repeated his important experiments on the density of the va- 
that proof is given the assertion amounts to a pure hypothesis. Among 
other difficulties, the following is suggested to the partisans of the so 
called anomalous densiti 
(1. 
volatile compounds, the formule of which are respectively NH,S, ane 
NH,S, HS. Sulphid of ammonium represents 4 volumes of vapor; 18 
Increased, because, as Deville and Troost have shewn, as the argon 
Increase the vapor-densities diminish toward a constant limit, so that 
oéflicients of expansion must also become constant and differ insens re) 
from 0°0367. To admit that the coéfficient of expansion of sire 
phosphorus vapors may be different from this number, in order to 
i 
: 
ty 
Ss 
