W. Gibbs on the Constitution of Organic Compounds. 35 
C+H302.H 
C2H ( , 
C1H302. H ae 
Ceo : 
Lactid, CcoHsO4, may be reduced to the type of two equivalents 
of water, and is rationally 
C+H302 } G, 
C2H jy ~~ 
to lactamic acid. a ; 
Malic acid—Some idea of the rational constitution of malic 
acid may be obtained from an attentive consideration of the pro- 
ducts of its decomposition. Caustic potash at a high tempera- 
ture converts the acid into oxalie and acetic acids, two equiva- 
lents of oxygen being required for the oxydation, since we have 
the equation 
OsHeOw-+-20 =01H101+-0:H208. 
Bromine decomposes the acid with formation of bromoform. 
According to Vauquelin, nitric acid converts it into oxalic acid. 
A ak acid gently heated with the acid yields carbonic oxyd 
and, according to Liebig, acetic acid. Finally, a mixture of sul- 
phuric acid and bichromate of potash converts all the carbon 
into carbonic acid. I refer malic acid to the type of six equiva- 
lents of water, and consider it to contain either formyl and form- 
se or glyoxal and formyl, so that its rational formula will be 
either 
C4+H204 C2oHO2 
OH O2HO2 
is C2H 
Ha 
If we admit that two equivalents of formoxyl, C2HO:, may be 
So fused together as to form one equivalent of glyoxal, we may 
suppose that two of formyl, C2:H, may unite to form one 
equivalent of a diatomic radical having the formula CaHe. 
this case the rational formula of malic acid, still referred to the 
type of six equivalents of water, will be 
CiH204 
(8.)  CaHe ton 
He 
In his memoir on glyoxal and its derivatives, Debus has sug- 
gested that a relationship betweep glycolic, malic, citric, gly- 
oxylic and tartaric acids, may be traced by means of glyoxa 
Without however attemptin g in this way to express the rational 
