36 TESTIMONY OF CHARLES F. CHANDLER. 



CHARLES F. CHANDLER, sworn and examined by Mr. PRENTICE : 



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



Q. Please state your study and preparation, and your acquaint- 

 ance and experience with chemistry and that which belongs to your 

 profession? A. I went to the Lawrence Scientific School at Cambridge 

 in 1853, remained there till the spring of 1854, and spent a year at 

 the University of Goettingen in Germany and a year at the Univer- 

 sity of Berlin, pursuing the study of chemistry in all its branches. 



Q. You took a degree, did you, there ? A. Took a degree of 

 doctor of philosophy at Goettingen. 



Q. Since that time you have been a professor in various insti- 

 tutions ? A. I have. 



Q. Please state where ? A. For about eight years at Union 

 College, and twelve years at the School of Mines in Columbia Col- 

 lege ; also for ten years at the College of Pharmacy in the city of 

 New York, and for the past three or four years at the College of 

 Physicians and Surgeons in New York. 



Q. The lactometers in use by the Board of Health are tested in 

 your laboratory, are they ? A. They are, under my direction. 



Q. This thermometer which was in evidence this morning, and 

 laid upon the table and taken up by you, has it been tested by you? 



(Thermometer shown to the witness.) 



A. It has been tested by me and found to be accurate. 



Q. That is the one used by Dr. White, was it, this morning ? 

 A. It is. 



Q. You were present at his examination ? A. I was. 



Q. Now, sir, have you made milk a special study ? A. I have, 



Q. Tell me, what is a lactometer ? A. A lactometer is an instru- 

 ment which belongs to the class of instruments called hydrometers. 

 It is a hydrometer specially graduated to suit the investigation of 

 milk for police purposes. All hydrometers are floating instruments 

 based upon the principle that when a solid substance is placed in 

 a liquid it sinks until it has displaced its own weight. The lighter 

 that liquid is, the deeper it must sink in order to displace its own 

 weight. The heavier that liquid is, the sooner it reaches a point 

 at which it has displaced its own weight. I have a diagram* of a 



* See cut on page 37. 



