68 TESTIMONY OF CHARLES F. CHANDLER. 



Q. Who invented the hydrometer, Doctor? A. That is more 

 than I can say. 



Q. You are quite sure that Dinocourt invented the lactometer ? 

 A. I won't say that some one else may not have suggested it ; 

 Dinocourt's glactometer, as it is called. 



Q. A milk at the specific gravity of 1.029, how does the selection 

 of that standard favor the milkmen ? A. Because by using the 

 lactometer at 1.029 for the 100 mark, no mistake is ever made of 

 arresting a milkman for selling Avatered milk, when he might have 

 been selling milk from an abnormal cow. 



Q. Is it not possible that a milkman arrested for selling milk at 

 88 or 90 might have been selling from an abnormal cow ? A. Not 

 mixed milk, city milk ; if a milkman should bring one, two, three or 

 six quarts of milk from a sick cow to New York, he might in that 

 way sell abnormal milk, which would stand below 100. 



Q. Now, Doctor, suppose you mix two quarts of milk at a specific 

 gravity of 90, and two quarts at the specific gravity of 100, and 

 two at the specific gravity of 110, what specific gravity will result 

 from that mixture ? 



(Objected to ; objection sustained ; exception.) 



Q. How do you determine an average specific gravity of mixed 

 milks in equal quantities ? A. By means of the lactometer. 



Q. "Well, do you determine the average by calculation ? A. No, 

 sir ; we insert the lactometer into the mixture. 



Q. Will you point out whether in those tables made by your 

 subordinates they did not adopt another method, that of calculating 

 between all the extremes? A. You asked me how to determine the 

 average of mixed milk ; these milks were not mixed ; the report here 

 is the average observations and not an average of mixed milks ; they 

 made say a dozen determinations of specific gravity of as many 

 samples of milk and then represented these observations by an 

 average, some 100, some 105, some 110, some 115, and some 120 ; 

 you add them together and you get an average ; not the average of 

 the mixture of the milk, but of the observations. 



Q. Milk mixed together originally of Different gravities is the 

 mean between the extremes of those gravities, the true average 

 specific gravity ? A. It would not be certainly, because in the first 

 place there are different quantities. 



