140 Agricultural Experiment STATioi«, Ithaca, N. Y. 



This aerator, when kept filled with water, will cool from 225 

 to 250 pounds per hour down to the neighborhood of sixty degrees. 

 The differences pointed out by the above figur(js seein to us to 

 very fairly indicate the relative merits of the two machines; both 

 are veiy nearly alike so far as ease of keeping clean is concerned. 

 Where running water is not at hand we should prefer the Cham- 

 pion; with running water, the Star. 



The Powell aerator is intended to aerate without cooling. We 

 have found that air may be kept constantly bubbling through a 

 forty-quart can of milk as it is drawn from the cow for live 

 minutes without cooling it more than two to four degrees. 



Several tests of the keeping quality of milk that had been 

 aerated by the several aerators and that which had not been 

 aerated at all were made. From the milk as it came to the 

 dairy -house a half -pint bottle was filled. Different portions were 

 then passed through the aerators and half -pint bottles filled 

 from them. These bottles uncorked were left exposed to the air 

 in the work-room of the dairy-house. Three times a day they 

 were shaken and tested with litmus paper and by tasting until 

 they were found to be perceptibly acid. 



