CATTLE PRODUCTS 357 



In making the test a definite, or measured, amount of 

 milk is put into a bottle with a long, narrow neck and just 

 enough acid is mixed with this to set free the fat. After the 

 fat is brought to the top by the whirling force, some hot water 

 is added to fill the bottle up to the neck. A second whirling 

 brings the fat above this water. A little water is again added 

 to float the fat up even with the scale on the neck of the 

 bottle. The third whirling gathers all the fat together in 

 the neck of the bottle so that the length of the column of 



i 



PIG. 223. Glass-ware and machine for making Babcock test for butter fat in 

 milk, cream, and skim milk. (Experiment Station, Wis.) 



the fat may be read on the scale. The neck must have been 

 correctly scaled, to give the result in percentage of the 

 amount of milk first put into the bottle. Thus if the fat 

 fills four full spaces of the neck of the bottle, the milk 'is 

 four per cent fat. 



Details of the Test. Sampling. Shake or otherwise 

 mix the samples to be tested just before beginning the work. 

 It must not be hot nor very cold. Measure out 17.6 cc. 

 (cubic centimeters) by drawing milk into the long pipette 

 (Fig. 223, P), just up to the mark. Suck the milk into the 

 pipette with the mouth; put a finger over the top and let 

 enough drip out until the top is exactly even with the mark. 



