4 1 o C HE MI ST R Y OF THE DIGESTIVE PR CESSES. 
hemialbumoses (or otherwise to the non-existence of cleavage at the 
albumose stage into hemi and anti groups). Nor, when these hemi- 
albumoses were subjected to more prolonged digestion yielding hemi- 
peptone (?), could this substance be completely broken up by prolonged 
tryptic digestion. 
Kiihne 1 also described as hemialbumose a substance occasionally found in 
the urine of patients suffering from osteomalacia, and first discovered by 
Bence Jones. Much has been made of the importance of this albumose by 
the supporters of the cleavage theory, but there is no more evidence that it is 
a pure hemialbumose than there is in the case of the substances described 
above ; that is to say, it has not been shown to be completely broken up by 
tryptic digestion, and this is the crux of the whole question. The fact that it 
yields leucine and tyrosine proves nothing. It has not been experimentally 
shown that no peptone is left after the prolonged action of trypsin upon it. 
Separation of the various albumoses from the "hemialbumose" pre- 
cipitate. — Stimulated by a desire to obtain a pure hemialbumose winch 
should be capable of complete decomposition past the peptone stage by 
trypsin, and encouraged in the belief that hemialbumose was a mixture, 
as well by the known existence of two physically different forms (the 
soluble and insoluble described above) as by certain inconstancies in its 
behaviour towards sodium chloride, Kiihne and Chittenden 2 set to work 
again upon the subject, and although they did not quite achieve their 
object, produced a research which, whether the cleavage theory stands 
or falls, must, from the experimental point of view, always remain of the 
highest value, containing as it does the first basis for a classification of 
the albumoses, the first light cast upon the relationship of this class 
of proteids. 
From the hemialbumose described in their previous paper, they were 
able to separate, by the action of sodium chloride under various 
conditions, four substances with the following properties : — 
1. Protoalbumose. — Precipitated by saturation with sodium chloride, 
soluble in cold and hot water. 
2. Heteroalbumose. — Also precipitated by saturation with sodium 
chloride, but insoluble in cold and in boiling water ; soluble in dilute and 
in moderately concentrated saline solution. 
'■'>. Dysalbumose. — The same as heteroalbumose, but insoluble in 
saline solution. This solution was recognised to be merely a more 
insoluble modification of heteroalbumose ; each of the two substances is 
easily convertible into the other. Dysalbumose corresponds to the 
" insoluble albumose " of the earlier paper. 
4. De uter oalbumose is not precipitated by saturation with sodium 
chloride alone, but is precipitated by saturation with sodium chloride in 
the presence of acetic acid, and is soluble in water. 
These various albumoses were subjected to tryptic digestion, and it 
was found that none was a pure hemialbumose, — all yielded more or less 
unci mvertible peptone accompanied by leucine and tyrosine. A bigger 
yield of amido-acids was obtained from protoalbumose and deutero- 
albumose than from heteroalbumose ; indeed, the latter showed itself to 
be more an anti- than a hemi- body, while protoalbumose yielded very 
little peptone and an abundance of amido-acids. After this evidence 
1 Ztschr. f. Biol, Munchen, 1SS3, Bd. xix. S. 209. 
2 Ibid., 1884, Bd. xx. S. 11. 
