Chemistry and Physics. 215 
363°. The second, or /-modification is obtained by fusing the 
f to nd allowi 
first completely at a temperature of 39° 
cool. Long concentric groups of thin prisms are in this way ob- 
“i A on introducing a crystal of this form. It also is monoclinic 
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permanent form of them all, both aw and 6 erystals becoming 
y in a few weeks. The crystals are orthorhombic, show a dis- 
by heating any of the other forms to 42°, On cooling the sub- 
stance remained permanently fluid, though a fragment of either 
solid form caused crystallization at once. i 
this isomerism on the h othesis of Naumann, that physical mole- 
than the unstable. Hence the fusing points of the latter are 
lower, the specific gravity is less and the specific heat is greater. 
—ber. Berl. Chem. Ges., ix, 760, June, 1876. G. F. 
_6. Synthesis of Allantoin.—As pyruvic acid acting upon urea 
ives a homologue of allantoin, Grmmaux acted u 
glyoxylie acid in expectation of obtaining allantoin itself. One 
for eight e mass was extracted with boiling 
alcohol, and the residue was dissolved in twelve to fifteen timds 
tS weight of hot w On cooling beautiful crystals were 
de h on analysis the formula 
posited, whi 643 & 
Slyoxylic diureide. Its identity with allantoin was completely 
proved by its chemical reactions, by its solubility, — crystalline 
ss Te 2 
form, ete, The rational formula | \NHY is assigned 
' o—nH7© 
to it pte uthor.— (, R., lxxxiii, 62, July, 1876. _ & FB 
7. ‘gh Pressure Manometer.—M. L. CAILLETET, in a recent 
* 
oP erottion of the change of volume which a cylindrical reservoir 
