184 Milk and Its Products 
machine. In other words, the greater the inflow, 
the more cream and the thinner the cream; _ the 
smaller the inflow, the less cream and the richer the 
cream. These varations can only take place within 
comparatively narrow limits. If we increase the in- 
flow too much, we shall soon reach a point at which 
the milk passes so rapidly through the machine that 
the separation is not complete, and if we reduce the 
inflow to such a point that the skimmed milk outlet 
has a capacity of discharging the milk as fast as it 
flows in, we shall get a separation until the bowl 
becomes filled, and then all of the milk will pass 
out of the skimmed milk outlet in the same condi 
tion in which it enters the machine. 
The speed of the machine, also, affects the rela- 
tive amount of cream and its percentage of.fat. The 
size of the skimmed milk outlet being fixed, the 
faster the bowl is revolved the greater the capacity 
of this outlet will be, so that, the rate. of inflow 
remaining uniform, the faster the bowl is revolved 
the less proportional amount of cream we shall have, 
and the richer it will be in fat, and vice versa. It 
must be borne in mind, further, that the speed of 
the bowl is also an important factor in the complete- 
ness of separation, and that if the speed is slackened 
in order to get a greater bulk of cream, there will 
be danger of incomplete separation. 
Most of the machines have arrangements for reg- 
ulating the relative amount of skimmed milk and 
eream without changing the rate of inflow or the 
speed of the machine. In most of the machines 
