408 Scientific Intelligence. 
points are found to be proportional to the differences between the form- 
ulas ; thus the specific volumes of two different fluids differing in their 
formulas by x.C2He differ by nearly x.22. Isomeric fluids are found 
to have equal specific volumes. In numerous cases in which oxygen 
replaces an equivalent amount of hydrogen, the specific volume remains . 
nearly the same as before the substitution. ere appears however in 
hand, however, carbon can replace hydrogen in fluid compounds without 
producing a change of volume. e new researches confirm the re- 
sults already obtained, that it is impossible, in a general manner, to de- 
duce the specific volume of aliquid from its empirical formula, without 
regarding the direct results of experiment as inaccurate. It became 
therefore necessary to return to hypotheses on the rational constitution 
the premises. The views brought forward can therefore only be re- 
garded as presenting the simplest possible general expressions for the 
specific volumes of liquids. For this purpose Gerhardt’s classification 
appears to be an advantageous one ; the author’s mode of fepresenting 
the volume of the elements in fluid con Se is the same as that a 
ready employed by him (Ann., vol. xcii, 1,) but the numerical values 
of the specific volumes of carbon, hydrogen and oxygen are somewhat 
different from those formerly determined. 
The specific volumes of fluids, which may be considered as derived 
from hydrogen H has type, correspond very well with the values de- 
duced from observation if we take the specific — io carbon as 
55, that of hydrogen also as 5:5, and that of oxygen 
he specific volumes of those fluids which may be sonsitesel as de- 
rived from water H \ Oa as type, may be satisfactorily deduced by 
giving the values above mentioned to carbon and hydrogen, but attribu- 
ting to the oxygen, when it stands in water, as a specific volume of 3'9: 
2 eq. of oxygen within a radical have the specific volume 2X6.1=12°2, 
but 2 eqs. of oxygen outside of a radical have the specific sa 
2X39=78. e same iaivinptions serve for ae which m 
be deduced from multiples of water as types. For the sic 
of the specific volumes of compounds containing only carbon, hydro- 
gen and oxygen, the author employed his own determinations, but for 
those of compounds containing other elements he made use of the ob- 
servations of Pier 
Sulphur occurs in ‘its compounds in different ways, sometimes (1) re- 
placing the oxygen in the type fy ; O2 as in mercaptan, &c., sometimes 
(2) pTeriecing earbon within a radical, as in sulphurous acid compared 
carbonic acid, sometimes (3) replacing the oxygen within a ‘radi- 
ware as in sulphocarbonic acid compared with carbonic acid C202 O2= 
C2S2{ Se. In the first and second case the specific volumes of the sul- 
phur aes unds correspond satifactorily with the observations if we 
take the volume of sulphur as 11-3, but for the third case the _— 
velo of sulphur appears to be greater, namely, 
+ 
