Relative Amount Skimmed Milk and Cream. 111 
to 15 per cent will usually suffice), and a higher speed 
of the bowl, or both. 
Conditions affecting the relative amount of skimmed 
milk and cretin.— The relative amount of skimmed 
milk and cream is affected by the rate of inflow, 
by the speed of the bowl, by various special econ- 
trivances upon the machines themselves, and to a 
slight extent by the temperature of the milk. In 
the ordinary machine the size of the skimmed milk 
outlet is fixed, and therefore at a given velocity the 
outlet will discharge a nearly uniform quantity of 
fluid. If, then, the milk is turned into the bowl at 
such a rate that .8 of it escapes through the skimmed 
milk outlet, we shall have .8 skimmed milk and 
22 cream. If now we reduce the rate of inflow 
by .1, we shall get just as much skimmed milk as 
before, but only one-half as much cream; or if the 
inflow is increased }y .1, we shall get the same 
amount of skimmed milk and once and a half as 
much cream. If under the first conditions all of the 
fat was gathered into the cream, we shall have just 
as complete a separation as before, but will simply 
get a cream containing a greater or less percentage 
of fat, provided that the increase of inflow has not 
increased the total amount above the capacity of the 
machine. In other words, the greater the inflow, 
the more eream and the thinner the cream; the 
smaller the inflow, the less cream and the richer the 
cream. These variations can only take place within 
comparatively narrow limits. If we increase the in- 
flow too much, we shall soon reach a point at which 
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