172 
IOWA ACADEMY OF SCIENCES. 
MOISTURE IN THE WHOLE SEED. 
100 grams of the powdered seed, dried at 102 degrees to 
110 degrees lost 6.862 grams, 6.8 per cent. The above rep- 
resents the loss when dried to constant weight at 110° C. 
ASH IN THE SEED. 
Ten grams of the powdered seed gave 0.2655 gram of 
ash, or 2.65 per cent of ash. 
DETERMINATION OF FREE ACID IN THE SEED. 
An examination of the acid properties of the seed showed 
the free acid to be wholly tannic or gallo-tannic acid. An 
examination was made by means of a standard solution of 
sodium hydroxide in which 1 c.c. was equivalent to .01 per 
cent acid. Five grams of the seed required 52 c.c. of the 
standard solution, or 10.5 per cent of acid. The above 
determination was made by simply extracting the seed for 
some time without grinding it. A second determination 
was made by first grinding the seed and then extracting as 
before. In this case 5 grams of the powder required 59 c.c. 
of standard solution or 12.03 per cent of acid. These 
determinations with others prove that nearly all of the 
acid exists in the husk and not in the seed proper. 
EXAMINATION OF THE HUSKED SEED. 
Some difficulty was experienced in removing the husk 
from the seed. By adjusting a mill very loosely, it was 
found that the husk could be removed easily without 
injuring the seed. Several determinations gave an average 
of 60 per cent seed, 40 per cent husk. 
A determination of the moisture and ash in the hulled 
seed gave 4.93 per cent of moisture; 2.08 per cent of ash. 
DETERMINATION OF OIL IN THE SEED. 
The whole seed of the Rhus glabra contains two dis- 
tinct oils, one in the husk and the other in the seed 
