CHAPTER v.— PART II. 



Chemical Selection of Mothers. 



History of Chemical Selection. — While the phys- 

 ical selection of beets with the view to seed production 

 has its importance, it is always considered secondary to 

 the chemical selection, either in laboratory or on the 

 field. Dubrunfaut was among the first to insist upon 

 some method for the selection of roots rich in sugar; it 

 was he, who, in 1825, declared that, volume for 

 volume, the heaviest beets were the richest in sugar. 

 The roots were weighed in air and water, and the cal- 

 culated density thus obtained was sufficient for the 

 selection of roots that were subsequently to furnish 

 seed to the sugar manufacturers. The fact is, as before 

 stated, France during a period of years was the centre 

 for superior beet seed; Russia, Germany and Austria 

 imported their seed from French growers. In 1850, 

 Vilmorin published his pamphlet on the proposition to 

 increase the sugar percentage of beets. However, 

 some vears prior to this, other issues were discussed, 

 with considerable foresight in regard to the possible 

 future. Baths of saline water were used, the classifica- 

 tion being based upon the strength of the bath — the 

 roots were well washed before immersion, and those 

 sinking were kept for mothers. In justice to 

 ^^ilmorin, it is interesting to note that, in 1852, he real- 

 ized that his method was not exact. Why the salt 

 water baths are objectionable will be subsequently 

 explained. It is now generally admitted that the actual 

 s- 'ection of beets wth the view to seed production, 

 as now accepted, was in 1856, for then, for the first time, 



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