ILLINOIS STATE DAIRYMEN'S ASSOCIATION. i Q y 



into disuse, but occasionally it appears as a new and improved method. 

 This is largely due to the efforts of concerns which are selling a specially 

 constructed can known as a hydraulic cream separator. These cans vary 

 more or less in minor details, some of which have a somewhat compli- 

 cated internal construction, which, however, does not appear to have 

 affected the efficiency of the machine, but the principle is the same in 

 each case. In the operation, the milk is diluted with an equal, or with 

 a greater, bulk of water and the mixture is allowed to stand from one-half 

 to twelve hours, and is then skimmed by drawing off the skim milk. The 

 supposition is, that by diluting the milk, the water being lighter than 

 skim milk, and heavier than cream it would rise and take a position 

 between the skim milk and the cream, and while assuming this place, it 

 would thereby facilitate the rising of the fat globules. This, however, is 

 not the case, for if water is added to milk it uniformly mixes with the 

 skim milk and merely lesesns the specific gravity between the fat and the 

 water by diluting the remaining constituents of the milk, which tends to 

 lessen the difference. The advantages claimed for this method are, small 

 cost for the can, lessened labor, durability, and requires neither ice nor 

 the storage of such. Sometimes it is mentioned that a cleaner cream 

 is produced than by any other system, and if the machine is properly 

 manufactured all the cream can be obtained. From the results obtained 

 at the Illinois Experiment Station and others, we believe that the claims 

 for the hydraulic separator can be equalled by the deep setting system, 

 not taking the centrifugal system into consideration at all, and the thor- 

 oughness of the separation will be far superior to any hydraulic separator 

 if milk is set at a temperature below 40. To prove the correctness of 

 this statement, I compiled the result of a series of experiments which 

 have recently been carried on at cur station. For the shollow setting, 

 we have an average of .84 of 1 per cent, of fat left in the skim milk.. 

 For the deep setting .62 per cent, and for the dilution system .81 percent., 

 an approximate gain of 25 per cent, of fat with the deep setting system 

 over the dilution system. These show the relative amount of fat left 



