IMPROVEMENT OP THE SEED. 181 



have large tanks containing an enormous volume of 

 salt watei-, demanding consequently a great loss of time 

 and a considerable expense. Mr. WalkhofF considers 

 that if we ascertain a proportion between the quantity 

 of sugar and the saline elements, we can then make a 

 most excellent selection ; this should never be lower 

 than 75 per cent., in other words, in 100 of solid sub- 

 stance indicated with the Baurae's areometer, there 

 should exist at least 75 of sugar. Beets might in- 

 dicate much sugar and saline matter at the same time, 

 and would then have no practical value, as the propor- 

 tion between the two would indicate. 



The largest seed growers in France are Deprez & 

 Co., where the roots are selected according to the sugar 

 they actually contain. The tests are made under the 

 direction of Chas. VioUette' of the FaculU des Sciences 



' Mr. VioUette supposes the beet an exact surface of revolution, engendered 

 by the triangle ABC, and that the sugar contained increases in an arithmetical 

 progression from D to C. If L M be an infinitesimal cylinder parallel to the 

 axis C D, according to the above hypothesis the point 5, middle of the same, 



Fig. 36. 



will have an average amount of sugar for this small element. The same argu- 

 ment will apply to 0, when the cylinder having the axis D C is. considered. 



