110 Scientific Intelligence. 
His first researches had been made*on crystals of tartaric and ra- 
cemic acids. Each of these acids presents both kinds of hemihedrism, 
under the same crystallographic planes, one being the reverse of the 
other. But the two acids, the right- and the left-handed, afforded by 
racemic acid retain their peculiar hemihedral and rotatory properties 
in their compounds when the bases present are without action on polar 
ized light; the two series of sol are identical except in the hemi 
hedrism and the rotatory phenome 
But he has now made.the new ire dv bey, that if, in place of combin- 
ing these acids with bases inactive to polarized light, they are united 
with substances that affect the plane of ie Parek, in some way, all 
aig ceases. The corresponding compounds have no longer the 
same composition, nor the same solubility ; eh do they act in the 
same a when exposed to a high heat. Often the combination is pos 
sible with a right-handed substance, and impossible with the left- handed. 
equivalent with the ordinary bimalate of ammonia, which is active 10 
polarization; but the left-handed bitartrate enters into no combination 
with this bimalate. 
M. Pasteur cites a large number of examples of this kind, and ex: 
~ plains in a simple manner these Rg te phenomena. When the two 
tartaric acids, the right and the left, combine each with an optically 
inactive substance, such as potassa, the inactive substance modifies in 
the same manner the rotatory power of both compoun e two 
acids were identical or not superposable optically, and this is still 
true of the two compoun ut when the two acids are united to an 
active base, as cinchonine; arene i is in iE case an addition to the rota- 
tory power, and in the other a sudtra 
. Pasteur considers it probable fr ai right. handed substances — 
ve a corresponding left-handed condition, and reciprocally. | He 
d in troniformiag cinchonine and quinine into new isomerous 
bases which are inactive to polarized light 
On the relation of Specific Heat to Atoms.—The law of Dulong and 
Peti been extended through the researches of M. Garnier, who 
determined the relation that exists between the specific heat of water 
and that of a simple body on one hand, and between the atomic weight 
of water and that of the same body, on the other. 
If we divide the atomic weight of water 112°5 tino — 
rear by ee om number of the —— atoms, we 
by the focmet (1.0000 +0-0951=10: 5), we: ascertain that the e specific 
