208 TESTIMONY OF GEORGE F. BARKER. 



Q. Now, a lactometer graduated upon the scale of 1.029, as a test 

 for the specific gravity of pure cow's milk, what is your opinion in 

 relation to that ? A. My opinion is that any form of the hydro- 

 meter may be as accurate as any other instrument, and the lac- 

 tometer is no exception. 



Q. Now take it at the graduation of 1.029, now, sir, I ask that as 

 the scale for the testing of the specific gravity of pure milk, the 

 scale of 1.029 what is your opinion as to its reliability, or the pro- 

 priety of that grade ? A. As I understand the question, it is in 

 reference to this instrument ; I cannot tell by inspection what this 

 instrument is graduated for ; each instrument must be tested by 

 itself. 



Q. Now, sir, what would in your opinion be a proper standard 

 for a lactometer to test pure milk? 



(Question objected to by the defense ; overruled ; exception.) 



A. The specific gravity of 1.029, in my opinion, would be a cor- 

 rect figure of the minimum for the correct gravity of milk. 



Q. Do you know what the standard of the Board of Health is in 

 its lactometer? A. Not of my own knowledge. 



Q. Can it be pure milk, which has not been manipulated in some 

 way, if it stands below 100 degrees ? A. No, sir. 



Q. In experimenting upon milk, do the conditions under which 

 the experiment is made have any effect upon determining the 

 accuracy of the experiment ? A. They do. 



Q. If milk should be found at a temperature of 60 degrees 

 Fahr. to stand at 88 degrees on a lactometer graduated to the scale 

 of 1.029, what would that prove as to the gravity of the milk? A. 

 It would prove that some lighter substance had been mixed with it. 



Q. Which is the lighter, water or milk ? A. Water. 



Q. Would milk tested under such conditions standing lower than 

 88 degrees be pure milk ? 



(Question objected to by the defense ; overruled ; exception.) 



A. No, sir ; it would not. 



Q. If the milk which is tested has been cooled in an open pan 

 in water and not cooled by yourself, would you consider that to be 

 a safe condition in determining the accuracy of the instrument 

 which you were using? A. My confidence in the result would 

 depend entirely upon the confidence I had in the person making 



