THE DECOMPOSITION PRODUCTS OE PROTEIDS. 31 
elimination, in such a way that the first amount of ammonia might be 
considered to come from one of the amide radicles of the oxamide, while 
the second corresponded to the urea, and the third to the remaining 
nitrogen of the oxamide, then present as oxamic acid. 
After precipitating the barium with carbonic anhydride and sulphuric 
acid, he obtained, by distillation in a partial vacuum, a small quantity of 
acetic acid, traces of formic acid, and an essential volatile oil which he 
indentified as pyrrol contaminated with smaller quantities of methyl- 
pyrrol and ethyl-pyrrol. The remainder, which did not volatilise 
nor sublime at a low temperature, he termed residu fixe. By con- 
trasting the composition of this with that of the original albumin, 
and taking into account the substances already enumerated, he found 
that the essential action of the barium hydrate was that of 
hydrolysis. By repeated crystallisations from water, alcohol, and 
ether, he separated the constituents of his residu fixe and found 
they were amido-acids of two classes, which we may term A and B. 
A. These comprised over 80 per cent, of the total weight ; in them 
the proportion N:0 = l:2. They consisted of — 
1. Amido-acids of the series C n H 2n+1 N0 2 . 
These he called leucines. They included alanine (C = 3) in small 
quantities, propalanine or amidobutyric acid (C = 4), butalanine or 
amidovaleric acid (C = 5), both in considerable amount, and leucine or 
amidocaproic acid (C = 6), in very large quantities. Glycocine or aniido- 
acetic acid (C = 2) was not found. 
2. Arnido-acids of the series C n H 2n _ 1 N 2 0. 
These are amido-acids of the acrylic series, and were called leuceines. 
Here, too, the term which was most abundant is that in which C = 6, but 
bodies corresponding to C = 4 or 5 were also found. 
3. Amido-acids of the series C n H 2n N 2 4 , or some multiple of this. 
To these substances he gave the name of gluco-proteins, on account 
of their sweet taste. The most abundant of these were those in which 
C = 9 or 7, or some multiple of these numbers; but others in which 
C = 8, 10, and 11 w T ere also isolated. 
B. These comprised about 16 per cent, of the total weight ; in them 
the proportion N:0= 1:3, or 1:4, or 2:5. In this class were found — 
1. Tyrosine ; the amount of this was about 3*5 per cent. 
2. Tyroleucine, C v H u X0 2 , in about the same quantity. 
3. Very small quantities of glutaminic acid, C 5 H (J N0 4 . This is an 
optically inactive amido-derivative of one of the pyrotartaric acids 
(glutaric). 
Of these substances, Sehutzenberger found varying quantities, 
according to the degree to which the hydrolytic decomposition had been 
carried out. The more thorough the hydrolysation, the more leucines 
and leuceines were found ; but in earlier stages gluco-proteins were 
in excess. 
With other proteids he obtained corresponding results. Gelatin 
gave the same substances, with the addition of amido-acetic acid or 
glycocine ; 20 to 25 per cent, of this substance was obtained. 
He concluded that the albumin molecule, under the action of barium 
hydrate, loses ammonia, carbonic anhydride, acetic and oxalic acid, and, 
becoming hydrated, forms in the first instance gluco-proteins, mainly 
those in which C=9, or some multiple of this, and that on further action 
these are changed into leucines and leuceines. 
