56 DAIRY LABORATORY GUIDE 



these and to get the last traces of water down into 

 the graduated part, the tube C is held with the bulb 

 in the palm of the hand and the stoppered end away 

 from the body, raised to a horizontal position, and 

 swung at arm's length sharply downward to the side. 

 This is repeated a number of times until the dividing 

 line between the water and amyl reagent is very 

 distinct and no amyl reagent can be seen with the 

 water or vice versa. The tube should then be held 

 a short time with the stoppered end downward and 

 the amyl reagent in the bulb of the tube agitated in 

 order to rinse down any water that may be adhering 

 to the sides of the bulb. 



Reading the Test. The reading should not be 

 taken until the tube and its contents have cooled 

 so that very little warmth is felt. The water is in 

 the bottom of the tube, and when a 10-gram sample 

 is taken the percentage may be read directly. Read 

 to the lower part of the meniscus. 



Other than lo-Gram Samples. With butter very 

 low in moisture it may be desirable to take a 15-gram 

 sample, and with butter extremely high 5-gram 

 samples may be used. The reading multiplied by 

 ten and the product divided by the weight in grams 

 of the sample taken equals the percentage of water. 



Time Required. To make a determination, inclu- 

 ding weighing sample, requires from fifteen to 

 twenty minutes. 



