118 



MANUAL FOE SUGAR GROWERS. 



of fluid as the body itself weighs ; thus any floating 

 body will be more or less submerged as the fluid in 

 which it floats is less or more dense. This princi- 

 ple is applied to the construction of hydrometers, 

 which serve to measure the density of fluids by the 

 depth to which they are submerged when they are 

 floated in the fluid. Hydrometers 

 are usually made of the form shown 

 in the figure, and may be of glass or 

 metal; a scale marked on the stem 

 measures the amount submerged, 

 and thus the density of the fluid. 

 Hydrometers are made with scales 

 of various values, according to the 

 uses for which they are to be em- 

 ployed. 



The hydrometer commonly used on 

 sugar estates is graduated with the 

 scale known as Beaume's. In the 

 table on pages 139 and 140 is given 

 the quantity of sugar in solution cor- 

 responding to the various degrees 

 Beaume. 



For use in the West Indies it is most convenient 

 to have the hydrometer graduated to indicate from 

 6 to 12 B., this range covering the variations of 

 ordinary cane -juice, and on an instrument thus 

 graduated the marks are sufficiently wide apart to 

 admit of their being read with considerable accu- 

 racy. The use of instruments having a scale rang- 

 ing from to 50 or 60 B. cannot fail to be mis- 



FIG. 18. Beaume's 

 hydrom e t e r or 

 saccharometer. 



