GEBBEB METHOD. 



351 



found to be calcium sulphate. Its formation furnishes a some- 

 what striking proof of the large amount of calcium compounds 

 present in cows' milk. 



Gerber tube. One -half natural size. 



These rapid centrifugal methods have repeatedly been com- 

 pared with the gravimetric processes for fat determinations, 

 and the results have always proved to be in close agreement ; 

 the error being rarely more than Ol %. 



Determination of Total Solids. The principle of all the 

 methods is simply to expel water by heat from a known 

 amount of milk and determine the weight of the residue. 



