256 PROFESSOR ‘LIEBIG ON THE AZOTIZED 
Carbon. 6) 0 Ab iwi eee a7 
Nitrogen i:.14!yi.){)'s eer Og Sh, 
Dydrogen 2.44 See 8) 6D 
Oxyremist 22 si ee a 228 
The solution of gluten in acetic acid is turbid and mucous; 
ammonia and its carbonate precipitate that solution white, long 
before the acetic acid is neutralized ; the matter is not glutinous 
in this state, but may be drawn out into threads. Mixed with 
it there is a substance resembling birdlime, which may be re- 
moved by ether. Boussingault neglected to use zther in puri- 
fying these substances; but this cannot be the cause of the dif- 
ference in the carbon. The numerous analyses which have been 
made here, prove that the difference lies partly in the difficulty 
of obtaining these substances in a fine powder after they are 
dried: they are all tough and horny, and it is impossible to 
burn them completely with oxide of copper. It can only be 
done with the assistance of chlorate of potash, or by using chro- 
mate of lead. As to the greater proportion of nitrogen obtained 
by Boussingault, I must refer to what I have said at the begin- 
ning, that although the analyses with oxide of copper, accord- 
ing to the qualitative method, in the experiments of Drs. Will, 
Varrentrapp, Scherer, and Jones, did not give 18 per cent of 
nitrogen; they gave so much as 17° and 17°5, which is equal to 
6°9, 7°0, 7°2, 7°3 of carbon to 1 of nitrogen. When chromate 
of lead was used, the proportion of 1 to 8 was found in the last 
tube of gas collected. 
According to the quantitative method of analysis first described 
by myself, and followed by Mulder, the proportion was 8 equi- 
yalents of carbon to 1 of nitrogen. The same result was ob- 
tained, according to the new method of estimation, from the 
ammonia produced, which gives very accurate results, (Annalen 
of Sept.*) Gluten I consider to be a very variable ingredient 
of the flour of cereals, as rye, barley, buck-wheat, and also of 
the flour of lentils, peas, beans, and maize, which, when washed 
with alcohol, give out fatty and resinous substances, but very 
little gluten ; it contains an organic acid, which I have not suc- 
ceeded in obtaining pure. It is well known what a small quantity 
of acetic or of lactic acid is necessary to combine with albumen, 
or to coagulate casein, and that no method is known of separating 
* See New Method of determining Nitrogen in Organic Compounds, by Drs. 
Will and Varrentrapp, in the Phil. Mag. for March 1842, p. 216. 
