422 
R. P. WODEHOUSE 
point of the solution sufficiently to cause it to boil vigorously on the 
hot water bath. In this way the risk of heating it to too high a 
temperature was avoided. 
When this gliadin solution was allowed to cool a small part of the 
protein settled out in a gluey mass at the bottom, and part assumed 
the form of a fine suspension which would pass through filter paper 
and could not be removed by centrifugalizing. So it was warmed up 
enough to cause complete resolution and while still hot poured into 
the dialyzers and dialyzed against tap water for three days, using thy- 
mol as a preservative. At the end of this time the protein had all 
settled at the bottom. The supernatant fluid was discarded, the 
dialyzers torn open and the gliadin scraped off. At this stage the 
protein was light gray in color and resembled malleable rubber in 
consistency. It was thoroughly washed in distilled water, then cut 
up into fine pieces and digested successively with acetone and ether, 
absolute alcohol, ether, and dried over sulphuric acid under diminished 
pressure. When desiccation was complete it was ground in a mortar 
to a fine gray powder which could be used conveniently for making 
the tests in these experiments. 
The residue from the gluten, remaining after the extraction of the 
gliadin, was now soaked in five or six volumes of 0.2 percent KOH to 
dissolve out the glutenin. This solution formed a thick opaque white 
fluid which could not be filtered; it was centrifugalized at high speed 
for about one hour; this precipitated a considerable amount of insoluble 
material. The supernatant fluid was poured off and very carefully 
neutralized by adding i percent HCl. This caused the production of 
a voluminous curdy precipitate which reached a maximum at neu- 
trality to litmus and would readily redissolve if made slightly more 
acid. This precipitated glutenin was removed by centrifugalization 
and the supernatant fluid, which was found to contain a large amount 
of protein, was evaporated down to about one fifth of its original volume 
on the water bath; the small amount of precipitate which had formed 
was discarded and the solution dialyzed free from KCl. Since no 
further precipitate was formed the dialyzer was transferred to 95 
percent alcohol which reduced the volume still further and caused the 
appearance of a precipitate. Dialysis was continued in fresh baths 
of alcohol and finally absolute alcohol and when thus dehydrated the 
precipitate was removed, washed in absolute alcohol, ether and dried 
over sulphuric acid under diminished pressure. This gave a fine white 
powder which is called in these experiments ''artificial proteose^ 
