478 Proceedings of Philosophical Societies. (June, 
blance to saline compounds, and in which the phosphorous acid 
acts the part of the base. On this account he proposes to call it 
phosphatic acid, in order to recall the analogy which it has with the 
phosphates. 
The last term of the oxygenation is the phosphoric acid. The 
proportion of the phosphorus to the oxygen in it is as 100 to 124. 
It is obtained by the rapid combustion of phosphorus, or by the de- 
composition of water by the bichloride of phosphorus, and by 
various other processes. It is identical with that which is obtained 
from the bones of animals. 
Three Dutch chemists, MM. Van Marum, Dieman, and Paéts 
Van Troostwick, made known in 1796 a gas composed of carbon 
and hydrogen, which they called olefiant gas, because its most sin- 
gular property was that of forming an oily liquid when mixed with 
oxymuriatic acid gas. From the theory of oxymuriatic acid at that 
time prevalent, the natural opinion was that its oxygen uniting with 
the olefiant gas constituted the oily liquid in question ; but at pre- 
sent, when this gas is considered as a simple substance, to which 
Davy has given the name of chlorine, we are under the necessity of 
looking out for a different explanation. MM. Robiquet and Colin 
undertook that investigation. They ascertained that when one 
volume of olefiant gas and two volumes of chlorine are made to mix 
slowly in a glass globe they are converted entirely, and without 
residue, into an oily liquid; which, when decomposed. by heat, 
gives hydrogen not saturated with carbon, a deposite of carbon, and 
much muriatic acid ; that is to say, according to the new theory, 
chlorine united to hydrogen. Hence it follows that chlorine enters 
entirely into the composition of the oily liquid. But does it enter 
in the state of chlorine, and unite directly to the carbureted hydro- 
gen? or is it united with hydrogen, and in the state of muriatic 
acid? The authors have been led to the first of these conclusions 
by inductions drawn from the specific gravity of the constituents 
and the compound; while muriatic ether, which has numerous re- 
semblances with this oily liquid, appeared to them, on the contrary, 
formed by the union of muriatic acid with olefiant gas. 
M. Chevreul still continues to labour with the same zeal at his 
chemical history of fat bodies. We have described after him for- 
merly that hog’s lard is composed of two principles—one more con- 
sistent, the other more liquid; that the action of the alkalies alters 
the combination, separates a new principle analogous to Scheele’s 
sweet principle of oils, and occasions the formation of two new 
principles of an acid nature, with which the alkali combines in 
order to form soap. We have explained the different affinities of 
the alkalies and earths for these two acids, and the capacities of 
saturation of the acids. Lastly, we have given an account of the 
comparative examination made by Chevreul of the different bodies 
more or less analogous to fat ; such as the biliary calculus, sperma- 
ceti, and the adipocire of dead bodies, and of the essential diffe- 
rences which characterize them. In a memoir presented to the 
