pa. 
UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 867 Ys 
Contribution from the Bureau of Plant Industry ‘yy 
WM. A. TAYLOR, Chief 
Washington, D.C. PROFESSIONAL PAPER September 3, 1929 
THE CASTOR-OIL INDUSTRY. 
By J. H. SHraper, formerly Chemical Technologist, Office of Drug, Poisonous, and 
Oil Plant Investigations. 
CONTENTS. 
Page. Page. 
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The inspection or valuation of castor beans. - fe | eCONnCiisions aoe ee ee eee Sats cekices se 40 
Manuiactie:of castor Oil. 3. 2. 2-5-5 2. 55. 9 
THE SOURCE OF CASTOR OIL. 
Castor oil is obtained from the seeds of the castor-oil plant (Rici- 
nus communis), a member of the plant family Euphorbiacee, 
which also includes many other species the seeds of which yield fatty 
oil. The castor-oil plant is now either cultivated or found growing 
wild in most tropical countries and in the milder parts of the Temper- 
ate Zones. In warm countries it is a perennial and often attains 
the proportions of a tree, frequently reaching a height of 40 feet, 
but in colder climates it rarely grows 20 feet high and annually dies 
down with the approach of winter. This plant is extremely variable 
in size, color of stems and leaves, degree of branching, size and color 
marking of the seeds, and many other characteristics. 
The seeds of the castor-oil plant are known as “‘castor beans”’ in 
English-speaking countries, and are often mistakenly supposed to 
belong to the bean family, to which they are in nowise related. Cas- 
tor beans as they occur in commerce consist of a white, soft, nonfi- 
brous kernel inclosed in a hard, thin seed coat. This is so brittle 
that unless care is exercised in handling, it is easily cracked and 
chipped off, exposing the kernel to the air, with attendant deteriora- 
tion. This seed coat is usually mottled in appearance and varies 
in color from a creamy white through pink, golden yellow, green, and 
182601°—20——1 
