Physics. 409 
dric acid and ammonia, because both of these are — 
Ww. G. 
[Wote.—It is easy to see that if the existence of 8-volume vapors be 
admitted, the molecular weights of the elements must be made to cor- 
respond to 8 volumes instead of to 4, provided that we assume, with the 
followers of Gerhardt and Laurent, “that the molecules of all substances 
science may lead to the adoption of the new atomic w weights, it is not to 
be denied that the advantage of simplicity still remains with the older 
view, which admits the possibility of a difference in the atomic Bees 
of different gases. G. 
n the ia of elastic bie —In a very interesting and sgyeasivs 
note on the course to be pursued to discover the ee truly universal prin- 
ciple in iiss nature, ae asserts that he has recently demonstrated, 
with an unhoped for degree of rigor and simplicity the following proposi- 
tions. The velocity of propagation of a plane wave in an solid diaphanous 
comparable to the breadth of the wave. In other words, in the formulas 
employed the coefficients of elasticity, instead of being constant, must 
contain the length of the wave and diminish with it ; this modification 
: ‘ ‘ 
and no 
secondly, the only completely rational explanation of the phenomenon of 
eepereney and thirdly, a whole series of new nye on dispersive 
powe n the coloration of transparent media, on the real distances 
which separate the ponderable particles and on other pilates Bes Mondes, 
4 Juin, 1863. Ww. 
3. On the atomic constitution of liquids—Wuaenzr has given an ex- 
planation of the motion of small sit of inapimate matter in liquids, 
