178 



Testing Milk and Its Products. 



his rule and records the depth of the cream in the can. 

 in inches and tenths of an inch. The cream is then 

 stirred thoroughly with a ladle or a stout dipper, and 

 sampled by filling a test tube to the graduation mark 

 by means of a small conical dipper provided with a 

 lip. A driver's case contains either two or three 

 "cards," holding fifteen test tubes each (see fig. 57). 



The tubes as filled are 

 placed in the case and 

 the corresponding num- 

 ber in each instance re- 

 corded in front of the 

 patron's name, together 

 with the number of 

 inches of cream fur- 

 nished by him. 



On the arrival at the 

 creamery the tin cards 

 holding the tubes are placed in a vessel filled with 

 water of the churning temperature (say, 60° in summer 

 and 65° to 70° in Avinter). When ready for churning 

 they are placed in the oil-test churn (fig. 56), the cover 

 of the churn put on, and the samples of cream churned 

 to butter. On the completion of the churning, the cards 

 are transferred to water of 175-190° Fahr., where they 

 are left for at least ten minutes to melt the butter and 

 "cook the butter milk into a curd." The oil will now 

 be seen mixing through the mass. The test tubes are 

 then cooled to churning temperature and churned 

 again, by which process the curd is broken into fine 



Fig. .57. Creiim-gatherer's 

 sample case. 



