10 July. 1918.] The Bahcork Tester on the Farm. 



401 



not mix thoroughly by shaking, until it is heated. Stand the sample 

 bottle in water, of a temperature from 100 to 110 degrees Fah., until 

 the cream is softened; then agitate gently until it is thoroughly mixed 

 with the milk, no small lumps remaining. The milk must then be 

 cooled to between 60 and 70 degrees Fah., which is the correct tempera- 

 ture at which to mix the milk and acid in the flask, both being as nearly 

 as possible at the same temperature. 



1.- — Six-bottle Babcock Tester. 



2. — Milk Scales. 



ISTow take 17.6 c.c. milk, giving the sample a shake first, and run 

 this into the flask ; to this add 17.5 c.c. sulphuric acid. When running 

 in the milk and acid, hold the flask in a slanting position and allow the 

 liquid to run gently down the inside of the neck. Shake the flask with 

 a rotary motion until all the curd (casein) is dissolved. Place the flasks 

 in the machine so that they balance and rotate for five minutes at the 

 speed indicated on the machine. Fill up to the bottom of the neck with 

 boiling water, run for two minutes more, fill to within 5 inch of the top 

 of the neck with more boiling water, run for one minute, take the flasks 

 ■but of the machine and stand in a water bath (Fig. 4 K) at 140 degrees 

 Fah. for a few minutes. Then read off the tests. The butter fat should 

 now be separated and collected in a clear compact column, like olive oil, 

 in the neck of the flask on top of the water. 



Reading the test. — By the illustration (Fig. 5) it will be clearly seen 

 how the flasks are graduated. Each division marked by long lines and 

 numbered, represents one per cent., and each division between marked by 



