MILK RECORDS 89 



avoided by adding the hot water in two portions, 

 filling the bottles at first only to the neck, and after 

 whirling about one minute adding sufficient hot 

 water to bring the fat into the graduated neck, after 

 which the bottle should be whirled and the fat 

 measured. 



If a steam-power machine is used it will not be 

 necessary to place the bottles in hot water. 



The percentage of fat is determined by the grad- 

 uated scale on the test tube. A pair of dividers or 

 small compasses (Fig. 4) can be used to good ad- 

 vantage in reading the results. The two points are 

 carefully adjusted, so they exactly enclose the fat 

 column. The lower point is then placed at the zero 

 mark ; the other point will then indicate the exact 

 reading. 



The result obtained gives the percentage of butter 

 fat in the milk. To determine how many pounds of 

 butter a cow is producing, multiply the pounds of 

 milk produced by the percentage of butter fat, and 

 multiply the result by I 1/6. 



EXAMPLE : 24 (pounds milk) X 0.04 (per cent, fat) 

 =0.96. (pound fat) X I 1/6= 1.12 (pounds butter). 



Record board. The accompanying cut (page 88) 

 represents a record board designed by the author at 

 the New Jersey Experiment Station. A record sheet 

 of sufficient size to include the weight of the morn- 

 ing and evening milk of each cow in the herd for a 

 month is attached to this board by means of thumb 

 tacks. Two panes of glass (a-a) are set in the frame 

 in front of the record sheet with a space (b) of 

 three-fourths of an inch between them for entering 



