22 SUGAR-BEET SEED 



as that facilitates the manipulation of the juices in 

 factory treatment. When sent to the laboratory, 

 each beet has a vertical hole drilled into it reaching 

 to the center, and the extracted pulp is weighed and 

 divided into not less than three samples, each of 

 which is analyzed. The laboratory tests give the 

 per cent, of sugar in the beet and in the juice, the 

 dry extract of the juice and the purity coefficient or 

 solid substances other than sugar.* To prevent de- 



* In the juices of the beet are many salts, or solids, in 

 solution. The solids, other than sugar, are called impurities 

 and these impurities act as a resistant to the process of extracting 

 the sugar. As the sugar and other solids are made in the field 

 and not in the factory, it is important to know the proportion 

 between sugar and total solid substances and to breed for higher 

 sugar content. If a beet contains 18 per cent, of solid substances, 



N 16X100 

 of which 1 6 per cent, is sugar, then - = purity coefficient 



Io 



= 88.8. Not less than 80 per cent, of the solid substances should 

 be sugar. In 1915 the average purity coefficient of beets grown 

 in California was 82.65; Colorado, 84.84; Idaho, 87.14; Michi- 

 gan, 84.08; Utah, 85.06. In Germany, the purity coefficient 

 rarely falls below 87 and frequently exceeds 90, and therefore 

 from a given grade of beets showing a like polarization, the 

 extraction of sugar per ton of beets is greater in Germany than 

 in the United States. In a technical article in "The Beet Sugar 

 Gazette" of July, 1901, the writer states the effect of impurities 



