130 TESTIMONY OF ELWYN WALLER. 



ELWYN WALLER, sworn and examined by Mr. PRENTICE : 



Q. Dr. Waller, you are a chemist by profession ? A. I am. 



Q. And you are consulting chemist of the Board of Health, I 

 believe ? A. My title in the Board of Health is Assistant Sanitary 

 Inspector ; I have the work of analysis of the Board. 



Q. And you are one of the officers of the School of Mines, are 

 you ? A. I am, sir. 



Q. The Laboratory ? A. Yes, sir. 



Q. You have charge of the Laboratory ? A. I have charge of 

 one of the Laboratories. 



Q. How many students have you there ? A. At present, some 

 70. 



Q. How long have you been there ? A. I have been there as a 

 student since 1868. I was there as a student for two years, and, 

 since 1870, I have been there in one capacity or another ; in my 

 present position, I have been there since 1871. 



Q. You have had a number of samples of milk brought to you 

 by inspectors of the Board of Health, for analysis, have you not ? 

 A. I have. 



Q. And with the rate on the lactometer ? A. Yes, sir. 



Q. And have you made the analyses ? A. I have made the an- 

 alyses. 



Q. To test the lactometrical rate ? A. Yes, sir. 



Q. In how many cases ? A. In 73 cases, I think. 



Q. And what did you find ? A. I found that the analysis showed 

 that the lactometer was correct. 



Q. In all these cases ? A. In all these cases. 



Q. Have you tested the lactometers of the Board of Health ? A. 1 

 have tested them. 



Q. At what point, and how ? A. I have tested them at three or 

 four different points ; at some point near the 100, at a point about 

 10 or 12 to 15 degrees below that that is from 85 to 88 ; at about 

 75 to 78, to 65 to 68 for different ones. 



Q. When the lactometer has shown an excess of water, what has 

 the analysis shown ? A. The analysis shows a little more usually 

 than is shown by the lactometer. 



. The four lactometers that were in use here, perhaps the first 



