132 Testing Milk and Its Products. 



milk and this is poured into the white cup. The same or 

 another No. 10 shell is now filled twice with the the tab- 

 let solution and emptied into the milk in the cup. In- 

 stead of dipping twice with one measure or a No. 10 

 shell, a tin measure can be made holding as much as two 

 No. 10 shells, or the tablet solution may be made of 

 double strength ; that is, two tablets to each ounce of 

 water and the same sized measure used for both the milk 

 and the tablet solution. The liquids are then mixed in 

 the cup by giving this a quick, rotary motion, and the 

 color of the mixture noticed. If the milk remains white 

 it contains more than two-tenths of one per cent, of acid 

 and should not be used for pasteurization. If it is col- 

 ored after having been thoroughly mixed with two 

 measures of tablet solution, it contains less than this 

 amount of acid and may, as far as acidity goes, be safely 

 used for pasteurization or for any other purpose which 

 requires thoroughly sweet milk. The shade of color ob- 

 tained will vary with different lots of milk; the sweet- 

 est milk will be most highly colored, but a milk retain- 

 ing even a faint pink color with two measures of tablet 

 solution, or one measure of the double strength solution 

 to one measure of milk, contains less than .2 per cent, 

 of acid. 



By proceeding in the manner described, the man re- 

 ceiving and inspecting the milk at the factory weigh-can * 

 is able to test the acidity of the milk delivered nearly as 

 quickly as he can weigh it ; and according to the results 

 of the test he can send the milk to the general delivery 

 vat or to the pasteurization vat, as the weigh-can may 

 be provided with two conductor spouts. 



