LACTOMETERS. 215 



to a specific gravity of 1'029. It is of no practical use ia milk 

 testing. 



Still another form is marked M at 1-029, and W at I'OO, the 

 intermediate space being divided into quarters ; this form is a 

 mere toy. 



An instrument has lately been put on the market, which con- 

 sists of a glass tube in which is enclosed a bulb of specific gravity 

 1"029, which floats in milk above this specific gravity, but sinks 



■Vieth's Lactometer. 



when the specific gravity is reduced below this figure by watering, 

 by warming, or by excess of cream. It provides a harmless 

 form of amusement, but is of no practical use. 



The best lactometers for use in milk testing are the thermo- 

 lactometer, Soxhlet's, and Vieth's. 



The thermo-lactometer cannot be made very small nor very 

 delicate on account of the enclosed thermometer, and requires 

 a comparatively large bulk of milk ; it is thus more suitable 



