TESTING CREAM 



THE BABCOCK TEST 



71 



tends from o to 25 per cent. Hence, in these bottles 

 we can use 18 grams of cream, provided the cream 

 does not contain over 25 per cent, of fat, while, with 

 cream testing over 25 and up to 50 per cent., a 9- 

 gram sample can be used for the test. In using this 

 form of bottle, care must be observed 

 when water is added near the close 

 of the test. Neither the lower nor the 

 upper surface of the fat-colunm nnist 

 be allowed to come in the bulb, since, 

 obviously, it is impossible then to read 

 the results. This style of bottle is also 

 made with a scale measuring 50 per 

 cent., the smallest divisions being .25 

 per cent. 



Straight-necked cream-bottles. — 

 The other varieties of cream-testing 

 bottles are straight-necked, varying in 

 respect to (i) diameter, (2) length 

 of neck, and (3) fineness of gradua- 

 tion. These vary in length from the 

 FIG. 30 ordinary size to Q and 10 inches, the 



STRAIGHT-NECKED , ' . . . . , 



CREVM -BOTTLE loi^S'^i" sizcs rcquirmg special testers. 

 In capacity, the necks vary from 6 to 

 20 cc, which is equivalent to 30 to 100 per cent., when 

 an 18-gram sample of cream is used. In fineness of 

 graduation, the smallest divisions vary in different bot- 

 tles from .2 to I per cent. One type of straight-necked 

 bottle is shown in Fig. 30. For strictly accurate work, 

 bottles graduated to .2 per cent, should be used ; and 

 the use of bottles whose finest division is more than 

 .5 per cent, should be condemned, except for rough 

 work. 



