TESTING BY THE LACTOMETER 133 



then corrected, if the temperature is above or below 

 60 F. For example, the lactometer settles in milk, 

 which is at a temperature of 65 F., to the point 

 marked 29. Adding to the reading for correction .1 

 for each degree above 60 F., which in this case is .5, 

 the reading becomes 29.5. This means that the spe- 

 cific gravity is 1.0295. If the temperature of the 

 milk were 55 F., the correction is subtracted and 

 the reading becomes 28.5, equal to specific gravity 

 1.0285. 



THE NEW YORK BOARD OF HEALTH 

 LACTOMETER 



Description. This lactometer has been in common 

 use among milk-inspectors in the east- 

 ern and middle states. Its scale is quite 

 different from that of the Quevenne lac- 

 tometer, since it is divided into 120 equal 

 parts. Beginning at the top of the in- 

 strument, the zero point on the scale is 

 the point to which the lactometer sinks 

 in water; and the point is marked 100 

 to which it settles in milk of specific grav- 

 ity 1,029 at 60 F. (Quevenne reading, 

 29), the lowest limit supposed to belong 

 to normal milk. The distance between 

 the zero and 100 points is divided into 

 100 equal parts and the scale is then pro- 

 longed beyond the 100 mark for 20 di- FIG. 49 

 visions to 120. The instrument is used CYLINDER FOR 

 in the same way as the Quevenne lactom- LACTOMETER 

 eter in testing milk. 



