FIELD CROPS. 345 



per acre), while on the plat which received the application of the 3 fer- 

 tilizing substances a yield of 109.4 bu. was obtained. 



Sorghum : Its development as a commercial source of sugar, 

 C. L. Penny (Delaware Sta. Bid. 39, pp. 23, dgms. 3). — The work of 

 propagation commenced in 1894 was continued in 1897. Fields of sor- 

 ghum were grown for the station on 2 private farms — at Cape Charles, 

 Virginia, and Harbeson, Delaware. At the first place the varieties 

 McLean and Amber were grown, and on the other farm the same 2 

 varieties with Colman and Frame New in addition. The stalks at dif- 

 ferent cuttings were sent to the station for analysis and the determina- 

 tion of other data. During the season more than 2,800 stalks were 

 examined individually. The results are tabulated and discussed at 

 considerable length. . 



In 1897 the percentage of sugar in the jnice of Frame New ranged 

 from 6.81 to 15.93 and averaged 11.98; that of Colman ranged from 

 10.16 to 17.84 and averaged 14.62; that of McLean grown at LTarbeson 

 ranged from 10.71 to 17.35 and averaged 15.20; the same variety grown 

 at Cape Charles ranged from 6.69 to 19.05 and averaged 15.24; the 

 Amber grown at Harbeson ranged from 8.30 to 19.19 and averaged 

 15.74; and the same variety grown at Cape Charles ranged from 10.09 

 to 20.50 and averaged 18.15. 



A formula for calculating the quantity of sugar which can be manu- 

 factured from a ton of cane is worked out, which is as follows: "If the 

 percentage of sugar in the juice be diminished by 0.9 per cent and the 

 remainder be multiplied by the coefficient of purity, regarded as a frac- 

 tion, the product will express the pounds of pure sugar actually to be 

 crystallized from 100 lbs. of stripped and topped cane." 



The results of experiments with sorghum at the station and at other 

 stations are summarized in a table. 



"There has been within the period of 10 years, from 1888 to 1897, an undoubted 

 improvement in the cane, so that within that time the same variety, so called, has 

 varied more than have different varieties at the same time. There must, of course, 

 be differences of season and of soil more or less favoring or hindering a good crop, 

 yet despite these there has been an unquestionable rise in the quality of the cane, 

 and this must be attributed to judicious selection of seed for propagation." 



A diagram is given showing the probable amount of sugar which can 

 be crystallized from a ton of stripped and topped cane of Amber, 

 McLean, and mixed crops grown under different conditions, indicating 

 that "the several varieties, when compared on the basis of yield of 

 crystallized sugar, show much greater differences than on the basis of 

 sugar content. While on the latter basis the extremes are about as 

 3 to 1, on the former they are about as 5£ to 1. This, as has been 

 explained, is due to the fact that the proportion of sugar crystallized 

 varies approximately as the purity of the juice, and, secondly, that the 

 purity usually rises and falls with the sugar content." 



The selection of seed for propagation, and the various factors which 



