THE CENTRIFUGAL MACHINE. 155 



chine an inch or an inch and a half. This basket is filled 

 with milk to the very edge of this opening. In one minute 

 after it begins to revolve, I see the milk change color. It 

 becomes less and less opaque, and assumes a sort of bluish 

 white shade. It grows deeper and deeper in color for three 

 or four minutes, and in from eight to ten minutes I find by 

 experience that I have a stratum of about an inch of cream 

 on this wall of milk. 



Now, to get this cream out, we have two valves, invented 

 by Mr. Bond, who has them here, I think, on his machine, 

 both of which are connected with the spindle. The process 

 is a rather difficult one to describe ; and, without a black- 

 board, I don't know as it will do for me to attempt it. I am 

 afraid I should get confused myself, and I am sure I should 

 confuse you. I will simply say, that the skim-milk is let out 

 at the rear, by means of these valves, into a great tin dish, 

 which is about ten inches in diameter, or less in diameter 

 than the opening at the top of the basket. This pan, I 

 should say, is about three inches deep ; and on this pan are 

 two ears, just such as you see on an old-fashioned tin kettle, 

 perfectly straight. These extend into the milk, pass through 

 the wall of cream ; and by means of this tin pan, dropping 

 the milk into the centre of this machine, we bring the cream 

 forward, until finally it is released on top. Although tins is 

 not natural, the pressure is so great that we get a forced 

 gravitation, you know, and it is released on top, and thrown 

 over this rim, and caught in a receptacle which surrounds 

 the top of this basket. 



That is simply the whole process. Now the object of this 

 machine is simply to extract all the lighter fluid, or the 

 cream, from the heavier fluid, or the milk. Winkel, in his 

 definition of milk, describes it as a fluid in which the fats are 

 in a state of perfect solution as the milk is drawn from the 

 cow. Well, this cream, or oil, is separated from the skim-milk 

 by means of this forced gravitation, this centrifugal force, so 

 that we obtain by mechanical means, in a few minutes, what 

 it takes Nature from six to thirty-six hours to produce. I 

 know the practicability of the machine ; for I am handling 

 about two tons of milk daily, and run the machine from half- 

 past six in the morning until three o'clock in the afternoon. 

 I put up some of this cream in little pint bottles, and ship 



