24 



ANNUAL REPORT OF THE 



Off. Doc. 



EXERCISE IV. 



This oxeroiso to bo devoted to testinj; samples of milk brought 

 ill by members of the ehiss, and taken so as to show tlie ditt'erence 

 in the variations in the com{)osition of milk. To emphasize the value 

 of knowinj;' what eaeh cow is produciuj;' in return for the feed she 

 is consiiniinji,-, show how an approximate record may be kept with 

 little real work. 



Material required for keeping such records. 



A spring balance, good one costs |4.00 though a much cheaper one 

 will aiisM'er fairly well. 



Sample jars, one for each cow, may be common fruit jars or milk 

 jars, but should have covers. 



A Babcock Tester that need not cost over |5.00. 



The discovery of and removal from the herd of one or two cows 

 that are eating more dollars worth of grain, hay and pasture thau 

 they are producing milk and butter fat to pay for will many times 

 over pay for the labor and expense involved, especially when it is 

 recalled that some cows produce ^75.00 and fSO.OO worth of butter 

 fat for 135.00 or $40.00 Avorth of feed. 



A milk sheet, which may be ruled up on common brown paper as 

 follows: 



DATE. 



Name 

 of cow. 



Name 

 of cow. 



Name 

 of cow. 



Name 

 of cow. 



Thk Acid ok Alkalt Test. 



The most conspicuous change during the ripening of cream is the 

 change of the milk sugar into lactic acid by the growth of certain 

 species of bacteria, this change is commonly called souring. 



When certain alkalies are brought into the presence of acid, de- 

 tinite amounts of acid unknown willi the alkali, therefore, by using 

 alkali of a known strength the amount of acid in a definite quantity 

 of cream or milk may be measured, by adding enough alkali to unite 

 wilh all of the acid that has been formed. An indicator is a mater- 

 ial the color of which differs in acid or in alkali. Phenolphtalein has 

 this power, is colorless in acid and pink in alkali, and is used to 

 indicate when enough alkali has been added to unite with all the 

 aoid. 



