FARM DAIRYING 



milk will run out in proportion to the air admitted. 

 When the milk exactly reaches the line indicating 

 the proper amount for a test, quickly press down 

 the finger. 



A test is of little or no value unless it is in every 

 way accurate. 



Place the point of the pipette in the neck of the 

 bottle, but do not shove it in tightly; remove 

 the finger from the end, and the milk runs into the 

 bottle. Blow, to get the last drop. 



Pour into the acid measure 17.5 c.c. of com- 

 mercial sulphuric acid with a specific gravity of 

 1.82. When adding it to the milk, hold the test 

 bottle on a slant so as to allow the acid to run 

 down the neck and under the milk, and not fall 

 directly on top of it. 



By giving the bottle a gentle rotary motion, thor- 

 oughly mix the acid and the milk. Never point 

 the neck of the bottle toward your own face or in 

 the direction of any one else, as a violent or care- 

 less shaking may cause the contents to spurt from 

 the bottle. The contents of the bottle get very hot 

 by the action of the acid. The acid dissolves all 

 the constituents of the milk, except the fat, which 

 it heats and liberates. Sulphuric acid is danger- 

 ous. It eats holes in cloth and burns the skin. 

 When it is handled with care there is no cause for 



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