AVERAGE RESULTS OF ANALYSES OF SORGHUM, ETC. 215 



General Results of Analyses Bearing upon the Question of Available Sugar. 



By reference to the table giving the general results of all the analy- 

 ses of the several varieties of sorghum, in 1879, 1880, and 1881, the 

 aggregate number of analyses being 4,042, and the varieties analyzed 

 being about 40, these results having been obtained from as many 

 varieties by so large a number of separate analyses made in successive 

 years, the general conclusion reached appears established beyond ques- 

 tion. 



During the early stages of development of these plants, up to and 

 including the sixth stage, the available sugar is given as a minus 

 quantity, i. e., the amount of sucrose in the juice is less than the sum 

 of the glucose and other solids. Also, in the seventh stage, the availa- 

 ble sugar is practically none, being only .13 per cent, and this stage 

 represents the period when the seed is in the milky state. It is, then, 

 obviously absurd to exj^ect to obtain any sugar by working up the crop 

 until it has advanced beyond this condition toward maturity. 



It will also be observed in the table, that, during these early stages, 

 the amount of this minus available sugar remains nearly the same, the 

 average for the first five stages being — ■ 3.22 per cent; and also, that 

 the available sugar, after it first appears, rapidly increases in quantity, 

 and remains practically constant through the several subsequent 

 stages; and in this it agrees, as will be seen, with the development of 

 the sucrose, which, at a certain period, is very rapid, and afterward 

 nearly constant through the season, while, as has been remarked, the 

 sum of the glucose and solids is nearly the same throughout. 



In the table, is given the average of the determinations for each 

 stage of development for all varieties. 



In addition to the columns giving the average results of the several 

 determinations given for each variety, there is given a column showing 

 "what is termed the percentage of available sugar present in the juice, 

 i. e., the amount of sugar which may be obtained as sugar from the 

 juice, for, as is known, the amount of sugar to be obtained from any 

 specimen of juice, depends obviously upon the amount of sugar present ; 

 and not alone upon this, but also upon the amount of glucose, and 

 other matters present, since, as is well known, the effect of these is to 

 prevent the crystallization of a portion of the sugar present, and, 

 hence, to increase the relative amount of molasses, the molasses con- 

 sisting of glucose, water, mineral matters (the ash), and more or less 

 sugar, which practically can not be recovered as such. Now, this mo- 

 lasses producing (melassigenic) property of the several impurities present 

 in the juices of cane, sorghum, and beets, has been a subject of con- 



