GRAVITY OR DILUTION SEPARATORS. 



Several 3^ears ago, before the general introduction of sepa- 

 rators, when the deep setting gravity system of raising cream 

 was. the method in common use in the larger butter making 

 districts, there occurred in New England and New York a suc- 

 cession of very mild winters when the supply of ice, so necessary 

 in the deep setting systems, was very materially reduced and, in 

 some cases, entirel}^ cut off. To overcome the lack of ice it was 

 suggested that the raising of the cream could be facilitated by 

 diluting the milk with from one half to an equal volume of 

 water, and the claim was freely made that the separation was 

 then as complete as though the milk without dilution had been 

 set in ice water. The whole matter was quite thoroughly 

 investigated by several experiment stations, ^^ and the following 

 general conclusions quoted from the Cornell University Agricul- 

 tural Experiment Station Bulletin 39 have since been pretty 

 generally received as authoritative : 



* * Combining the results of this Station with the results at the 



Vermont Station, we have the following average percentages of 



fat in the skimmed milk under the different systems : 



Diluted, set at 60° (39 trials) .77% 

 Undiluted, set at 60° (30 trials) i.oo 

 Undiluted, set at 40° (26 trials') .29 



"It would seem therefore that while, when the milk is set at 

 sixty degrees or thereabouts, there is considerable advantage, so 

 far as the efficiency of creaming is concerned, in diluting it with 

 25 per cent of warm water ; this dilution cannot be regarded as 

 a substitute for setting without dilution in ice water, and it has 



* Vermont Agr. Expt. Sta., Newspaper Bulletin No. 3 and 4th Annual 

 Report, pp. 100-107. 



Cornell Univ. Agr. Expt. Sta., Bulletins Nos. 20, 29 and 39. 



University of Illinois Agr. Expt. Sta., Bulletin No. 12, p.' 376 and Bulletin 

 No. 18, p. 30. 



