36 



a periodical connection between the milk pail, and the pump 

 — if not overdone — has been quite a safe opex'ation, hitherto, 

 as far as the chances of detection are concerned. This impleasaut 

 circumstance was clearly demonstrated in a recent report of my 

 friend, Professor C. F. Chandler, of New York city ; in which he 

 states, that actual experiments induce him to beheve that the inhab- 

 itants of the cities of New York and Brooklyn, get their annual sup- 

 ply of mUk, which amounts to one hundred and twentj'' million 

 quarts diluted with forty million quarts of water, for which adulter- 

 ation at ten cents per quart, they pay four million dollars. I need 

 not to say that Prof. Chandler did not base his conclusion on the re- 

 sults obtained merely b}' the apphcation of any of the various areo- 

 meters for ascertaining the specific gTavity of milk. 



Farmers, who convert the milk of their cows, upon their own 

 gi'ounds, into butter and cheese, have probably little need of good 

 modes of testing milk, for the result of their dairy operations will 

 tell them sometime, at least, what their milk is worth. Outside 

 consumers are quite differently situated ; and a few remarks on some 

 of the modes of testing milk for commercial purposes may interest 

 them. The first instruments introduced for testing milk were 

 several arbitrarily arranged areometers. Doerffel's milk balance, and 

 Dinacourt's galactometer are fi-equently mentioned in this connec- 

 tion. Doerffel's instrument consists of an arometer with a scale of 

 twenty degrees. Zero implies water at 60*^ F., whilst 20 degrees 

 refers to a hquid of 1.0333 specific gravity, and is equal to 9.5 

 degrees of an ordinary saccharometer. The latter instrument may 

 be used instead of Doerffel's, their relations being expressed by the 

 following figui'es : 



Doerffel. Saccharometer. Spec. grav. 



11.0 5.1 



12.0 5.6 



13.0 6.1 



140 6.6 1.026. 



16.0 7.6 1.0310. 



17.0 8.1 1.0332. 



20.0 9.5 1.0333. 



Dinacourt's galactometer is also'an areometei*, but divided into 

 100 degrees. 100 degrees is equal 1.029 specific gra\'ity, which con- 

 centration is assumed to represent that of good milk ; zero indicates 

 pure water. For testing skimmed mUk a similar instrument is used 



