T’.. S. Hunt on the Constitution of Leucine. 67 
of ammonia and hydrogen by that agent from glycocoll, and 
found in the residue an oxalate ; its analogy with leucine would 
lead us to expect formic acid, but Peligot has shown that a formiate 
when fused with excess 0 potash, is converted with the evolution 
of hydrogen into an oxalate, so that the product of Mr. Horsford’s 
experiment was the result of a secondary action. 
When thus regarded, the isomerism of these two classes of 
bodies is already explained ; it is precisely that which exists be- 
tween the acetic methylic ether and the formic ethylic ether, two 
bodies scarcely distinguishable but by the action of an alkali, 
which converts the one into an acetate and methol, and the other 
ions a formiate and alcohol; the number of these isomeres is only 
limited by the want of the ‘higher alcohols. It follows then that 
there does not exist a homologue of urea in the first family, for 
here in this primitive species the two groups are confounded, and 
i farther it appears, that as we rise in the scale the number of pos- 
sible isomeres is greatly increased. In the third family we have 
regarded the compound of Wurtz as the binamid of the acid of 
that family, while the new urea is an amido-ethylamid of the acid 
of the first family; there may equally exist a bimethylamid of 
carbonic acid or an amido-ethylamid of glycocollie acid, all of 
which will be isomeric with metacetic urea. The discovery of 
in Various ways, to increase the number of homologues and iso- 
meric substances to an extent which is almost inconceivable. 
The action of nitrous acid upon urea is well known to result in 
its conversion into nitrogen and carbonic acid, which is at once 
composed into water and au anhydrid, and a similar process has 
been adopted by Piria in his beautiful researches upon asparagine ; 
he has demonstrated that in this way many amids are readily 
aan into nitrogen and a non-azotized 
- A similar process applied to glycocoll, sarcosine e and louieutie, 
ie would probably enable us to eliminate the acids of that series,* 
while the decomposition of the urethanes and higher ureas as 
Well as the new alkaloids under its action, still presents a curious 
subject for investigation. 
oreeaima May 22d, 1849. 
* M. Cahours has observed in the memoir — nones that when leucine is 
treated Lg oxydiing agents or solution, it is decomposed with 
the evolution of a ery disagree age ee r, and the forts ation ‘ot an acid which he sup- 
may be a homologue of the yeocollie, and he su ggests that sarcosine by a 
Similar process risen mrt the 24 ve Eis ere he ap} _* ae - ay é for the 
neutral lactates are legge 0 vg e ACe erhardt ) 
ile j i Bley the fi at ic ‘a Mae pol- 
ymert ic gH, Og. Lactic 
= _ se been described ve monobasie, bk Busclbardt and Maddsell in their 
arches upon its salts, (Liebig’s Annal, xiii, p. 83,) arrive at the conclusion 
that iti tis bibasic, apparently a. ba VL "Gerhardt had long before announced 
e thing, (Precis, tome ler, p. 596.) 
* 
