Ceeam Raising bt Dilihion. 110 



Undiluted set at 60 (5 trials), .82 per cent of fat in skim-milk. 



Undiluted set at 40 (7 trials), .44 per cent of fat in skim-milk. 



On the other hand, we have found (Bulletin No. 20, pages 

 62-65), in twenty- three trials with mixed herd-mUk, the folio wing- 

 average percentages of fat in the skim-mUk: 



Diluted set at 60 (10 trials), 1.11 per cent of fat in the skim-iaiik. 



Undiluted set at 60 ( 2 trials), .89 per cent of fat in the skim-mUk. 



Undiluted set at 40 (11 trials), .23 per cent of fat in the skim-mUic. 



It will thus be seen that the results at the Vermont station 

 from diluting and then setting at sixty were much better than 

 where the milk was not dUuted and set at the same temperature, 

 and nearly as good as where the undiluted milk was set at forty, 

 while at this station the results from diluting and setting at 

 sixty were not as good as from the undiluted milk set at the 

 same temperature and much poorer than from the undiluted milk 

 set at forty. This, then, was the chief point of difference in the 

 results obtained at the two stations and it was to this point par- 

 ticularly that the experiments following were directed. 



In all cases the milk was set for twenty-four hours before skim 

 ming. The analysis of the fat in the skim-milk was made by Mr. 

 G. W. Cavanaugh, assistant chemist of the station, by the Bab- 

 cock Asbestots Gravimetric method. The details of setting, 

 skimming and sampling, and the determining of the fat in the 

 whole mUk by the Babcock method were all done by the writer. 

 Cooley cans were used in all cases, and in skimming great care 

 was taken that there should uniformly be left one whole space 

 of sldm-mUk under the cream line; that is to say, the cream was 

 drawn down to the last mark but one of the scale. Bv far the 

 larger number of the tests were made with the mixed evening 

 milk of the University herd, consisting of grade Holstein and 

 grade Jersey cows, which had been in milk from three to six 

 months. A few tests were made with mUk from the Jersey cows 

 that were freshest and from the Holstein cows that^were longest 

 in mUk; these will be noticed in detail further on. In all cases 

 a full can twenty inches deep was used for each test, and in all 

 cases a diluted and undiluted can were set from the same milking. 

 In every instance where milk was diluted the percentage of fat 

 in the skim-milk is corrected for the amount of water added. 



