80 Water-Soluble B 
that the dietary unknown is not greatly reduced in amount by 
the heat treatment, for 10 per cent of cooked beans still supplies 
enough to support normal growth for 7 weeks. Rats do not eat 
rations which contain appreciable amounts of raw beans, so it is 
not possible to conduct comparable experiments with heated and 
unheated beans. The true explanation of these results is that 
apparently because of physical change in the beans during cook- 
ing alcohol fails to extract the water-soluble B after the heat. 
treatment. 
Preparation of Extracts Employed with Lots 973 A and 978. B.— 
918 gm. of navy beans (cooked) were extracted with ether for 18 
hours and then with alcohol in three consecutive 6 hour periods, 
removing the extract at the end of each period. The first two 
extracts were evaporated on 100 gm. of dextrin and the alcohol 
was removed. There was an increase in weight of 37.1 gm. 
The last 6 hours’ extract was evaporated on 50 gm. of dextrin 
giving 11.1 gm. of extract. The extracts were united and made 
up to 200 gm. with dextrin. 
100 gm. of the above preparation equivalent to 459 gm. of 
beans were extracted with benzene in three consecutive 6 hour 
periods, removing the extract at the end of each period. The 
extracts were evaporated in weighed crystallizing dishes. Weight 
of first extract, 9.80 gm.; second extract, 0.025 gm.; third ex- 
tract, trace. The extracts were taken up in benzene and evap- 
orated on dextrin. Final weight 91.8 gm. The alcohol-soluble, 
benzene-insoluble portion was fed to Lot 973 A. The alcohol- 
soluble, benzene-soluble part was fed to Lot 973 B, first, equiva- 
lent to 30 and later raised to 60 gm. of beans per 100 gm. of 
ration. 
Chart 9. Lots 999 A, 999 B, and 972 B. 
Lot 999 A. Period 1.—Ration: Purified food mixture plus 5 per cent of 
butter fat. 
Period 2.—Ration: Same as Period 1, but with the addition of the alco- 
holic extract of 10 gm. of ether-extracted cooked navy beans per 100 gm. 
of ration. 
Period 3.—Ration: Same as Period 2, but with the extract increased to 
make the equivalent of 30 gm. of cooked beans per 100 gm. of ration. 
Lot 999 B. Period 1.—Ration: Purified food mixture plus 5 per cent of 
butter fat. ! 
