208 
O' Brien . — The Proteids of Wheat. 
carried down a small amount of fat (? half), while the rest was 
left in the flour in the funnel : so that perhaps an excess of 
5-6°/ o of fat in gluten over that in the albuminate may be 
counted on. Von Bibra gives 5*85°/ o , Ritthausen 6°/ o , as the fat 
present in gluten. The residue of starch will vary with the 
nature of the gluten and the method of washing : — Ritthausen 
found i6°/ 0 in one sample, in one case I found about i2°/ o . 
Add to these facts, the difficulty of thoroughly drying gluten in 
masses, even of the size in question (about i gram), and the 
probable retention of a small amount of water ; and the 20°/ o 
difference between gluten and the albuminate will be fully 
accounted for. 
Hence the io f f of crude gluten may be considered as thus 
constituted at the time of formation : — 
Glian 7-14 grams (cf. C. p. 196) . 
Zymom 1*2 . 
Impurities 
2-2 
The glian and zymom together constitute what an earlier 
application of alcohol to the flour would have extracted as 
the 8-3 grams of albuminate. 
This may seem but a rough and ready way of working ; 
but, considering the rapidity with which these substances 
change during manipulation, and the difficulty in isolating 
them, it seems preferable to elaborate extractions with ether, 
and repeated solution in and reprecipitation from acid and 
alkaline solution. Even with all these at his command 
Ritthausen was only able to account for 7 0, 3°/o of his crude 
gluten as the pure substance (the rest being fat, 6°/ o ; starch, 
&c., i6°/ o ; loss, 7*7%). A confirmation of the approximate 
accuracy of their estimated composition is seen in the total 
proteid of the flour. 
The total nitrogen in the flour used (as estimated by 
Mr. Manley, of the Magdalen College Laboratory) is 1-761 °/ o , 
representing probably not more than jG-f6°/ o proteid. (This 
is obtained by using 6 as the co-efficient : the large amount of 
nitrogen in the proteids would according to Ritthausen justify 
