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easier of solution by the fact, which was pretty generally noticeable in 

 the work at this station, that purity of juice and a low content of glu- 

 cose generally accompany a high percentage of sucrose. Moreover, it 

 is generally the case, though this is not so constant, that a high density 

 of juice indicates high content of sucrose, low of glucose, and high 

 purity. The following analysis, taken from some of the individual 

 canes which gave the best polarizations illustrates this point. 



Analyses of canes showing high percentage of sugar. 



Rough selections therefore can be made by the hydrometer spindle, 

 throwing out all which do not come np to a certain standard. The 

 selections made in this way may then be polarized, and further selec- 

 tions made by this test, while the final selection should be based upon a 

 complete analysis. Considerable weight should be attached to the purity 

 as a basis for selection, for this is the weak point of sorghum as a sugar- 

 producing plant. Tt will be seen from the above analyses that these 

 canes were fully equal to tropical canes so far as a high content of sucrose 

 and a low content of glucose are concerned, but the purity is low in 

 proportion. The selection and comparison of canes for seed should be 

 made when the plot has reached its maximum of purity, as nearly as it 

 is possible to ascertain that point. Then the relation of high sucrose 

 content, high density, and purity, etc., is most likely to be normal and 

 constant. 



It will be seen that a course of selection, as outlined above, necessi- 

 tates the making of a great many analyses. Facilities for making a large 

 number of analyses, the more the better, would constitute an essen- 

 tial part of the equipment of a station for the improvement of the plant. 

 But undoubtedly a great deal could be accomplished in selection of seed 

 by the use of the hydrometer alone, where facilities for complete analy- 

 sis do not exist, until the time comes when seed improvement can be 

 carried out properly by separate stations or establishments. 



We believe that every large cane grower should test his canes in this 

 way, and should make selections of seed by the hydrometer test, unless 

 lie can use still better methods. Even this simple method of selecting 

 seed would be vastly better than the usual way of merely selecting seed 

 that is ripe and sound. If constantly practiced it would do much to re- 



