PHILOSOPHICAL SOCIETY OF WASHINGTON. 141 



and syrup had been frequently produced, yet the manufacture of 

 crystallized sugar had not on the whole been attended with much 

 success. Several years ago, Mr. J. Stanton Gould, of New York, 

 had suggested that a few systematic and careful experiments ought 

 to be made, but so far as known, none had been undertaken until 

 recently. In 1879, the Agricultural Department resolved to ex- 

 periment in this direction, and obtained seed for four varieties, the 

 Early Amber, the White Liberian, the Chinese and the Honduras. 

 These were planted May 15th, and a series of experiments was 

 made beginning soon after the flower appeared and repeated every 

 four or five days, until frost appeared in October. 



Full details in regard to these experiments will be given in the 

 annual report for 1879 of the Commissioner of Agriculture. The 

 following are the more important results : 



July 18th. The juice expressed from the Early Amber contained 

 four per cent, of crystallizable and 3} per cent, of uncrystallizable 

 sugar. 



August 15th. The juice contained 14.75 per cent, crystallizable, 

 ^nd I4 per cent, uncrystallizable sugar. The latter proportions 

 were maintained until heavy frosts in October. 



The same results approximately were shown by the White 

 Liberian upon the same dates. 



August 6th. The Chinese variety showed less than two per cent, 

 of crystallizable, and about five per cent, of uncrystallizable sugar ; 

 but with the progress of the season, the former gradually increased 

 and the latter decreased. 



The Honduras variety behaved in a manner very similar to the 

 Chinese, but developed still later, reaching a maximum on the 18th 

 of October. The general results of these experiments seemed to 

 show that the failure hitherto to obtain sugar from sorghum was 

 due to the custom of cutting the canes too early, and before they 

 were ripe. If they had been permitted to stand as long as possi- 

 ble, before the inception of change by the action of frost, the 

 amount of sucrose would have been much greater and the glucose 

 much less. 



