ii6 GUIDE TO DAIRYING IN SOUTH AFRICA 



is regulated to produce a 45 % cream and that of 

 the other a 34 % cream, and the only advantage 

 gained, from a financial point of view, by the sup- 

 plier who despatched a 45 % cream to the creamery 

 would be through the extra amount of skim milk 

 he would have available with which to feed his 

 calves and pigs. 



Table II. gives complete figures of a second 

 speed trial conducted in Pretoria. It will be ob- 

 served that when the machine was turned at the 

 correct speed of 60 revolutions per minute it pro- 

 duced cream containing 34 % of butter fat ; on the 

 other hand, when the speed was increased from 60 

 to 74 revolutions, the butter fat in the resulting 

 cream was increased to 52 %, thus showing that too 

 high a speed will increase the butter-fat content of 

 cream very considerably, just in the same way as 

 too slow a speed will correspondingly reduce it. 

 The figures in Table II. point to the fact that the 

 best result is obtained when turning the machine at 

 the correct speed. It must also be borne in mind, 

 that when a machine is being worked every day 

 under ordinary farm conditions nothing like the 

 low percentages of butter fat would be found in 

 the skim milk as are depicted in Table II. As 

 previously stated, if under ordinary circumstances 

 a separator only leaves o'io of i % in the skim 

 milk, then it is performing very good work. 



Fig. 13 gives a very good illustration of the 



