118 TESTIMONY OF BENJAMIN SILLIMAN. 



deeper in the fluid and consequently involve an error ; if you will 

 have the kindness to refer to the book which is already in evidence 

 before the court of yesterday, Bouchardat, you will find in it speci- 

 fic instructions given in the prefatory portion of that volume that 

 the most careful consideration and precaution should be used in 

 introducing the instrument into the milk to avoid the moistening of 

 the stem above the portion of the stem where it is expected to sink, 

 and with that explanation I say I see no difference between the use 

 of the hydrometer applied to milk or the hydrometer as applied to 

 oily materials or any other fluid. 



Q. Is any difficulty presented in examining milk by the hydro- 

 meter more than in the examination of other bodies ? A. I think 

 not. 



Q. In case a sample of milk stands when properly tested by an 

 accurate lactometer at 95 degrees, may not that be caused either by 

 the presence of too much water or too much cream ? A. It may. 



Q. How can you tell the change by the lactometer ? A. By the 

 consistency of the milk that is caused by water ; the milk will not 

 fail to distinguish itself at once by the familiar character of diluted 

 or skimmed milk ; it will be changed in color ; it will be changed in 

 consistency ; if the milk is so exceptionally rich in cream that it will 

 stand at 90 or 95 degrees of the hydrometer the least skilled ob- 

 server will not fail to distinguish at once the fact that the milk 

 is very greatly richer than average commercial milk. 



Q. Do you assert that by looking at the milk and exercising the 

 evidence of your senses towards it you can tell whether its low 

 gravity is caused by the presence of cream or by the presence of 

 water ? A. I think so. 



Q. Are you certain of that ? A. [Reasonably certain. 



Q. Are you quite certain ; I do not know what reasonably certain 

 means ? A. I should be willing to hazard my opinion upon it that 

 it was so. 



Q. Would you be willing to hazard anything more than an 

 opinion on that ? A. I would ; I would hazard my money on 

 it. 



Q. I suppose your opinion is worth more than your money? A. 

 No doubt, I should prefer to buy some milk of that sort for my 

 coffee. 



