Linseed Meal 245 



specks, because the presence of these indicate either 

 accidental or intentional adulteration with hulls. Cot- 

 tonseed feed, which appears to have found only a 

 limited use, is a finely -ground mixture of cottonseed 

 hulls and cottonseed meal, and its value is usually 

 much less than that of the pure meal. 



Linseed meal {oil meal). — The original source of 

 this feeding stuff is the flax plant. This plant serves 

 a very useful purpose in producing a valuable fiber, 

 an oil which now seems indispensable as a constituent 

 of paint and a high class stock food. Flaxseed, of 

 which the annual production in this country averages 

 about twelve million tons, contains a very high per- 

 centage of oil, ranging in the analyses so far made 

 from 22 to 40 per cent. The average is variously 

 stated by different compilers at from 33 to 37 per cent, 

 and the mean of these two numbers is probably fairly 

 correct. On this basis a bushel of flaxseed, weighing 

 fifty-six pounds, contains nineteen and one- half pounds 

 of oil and thirty -six and one -half pounds of other 

 substances. 



Linseed oil is obtained from the seed by both the 

 pressure and extraction methods. The oldest method 

 was to subject the cold crushed seeds to a heavy pres- 

 sure, which expressed from 70 to 80 per cent of the 

 oil, leaving a cake containing from 10 to 15 per cent. 

 Later the warm pressure process was introduced, which 

 consists of moistening the crushed seed, heating it to 

 from 160° to 180° Fahr., and submitting it to a pressure 

 of 2,000 to 3,000 pounds per square inch. This im- 

 provement increased the output of oil from a given 



