TABLES OF SPECIFIC GEATITY OF SOEGHTM JUICES, ETC. 489 



ses made have demonstrated, that if the total of glucose aud sucrose 

 in a juice is 14 or lo per ceut of the juice, at least 12 or 13 per cent 

 of this had existed in the plant as sucrose. If not present upon analy- 

 sis, it must have suffered inversion — as in this case Avas easily rendered 

 probable bv the stalks having been cut some days before they were 

 worked up iu the mdl. 



TABLES OF SPECIFIC GRAVITY OF SOEGHUM JTICES AXD THEIR COM- 

 POSITION. 



In the following tables are given average results obtained bv the 

 analysis of sorghum juices of different specific gravities, durino" the 

 yeai^ 1879, 1880, 1881, 1882. 



These give the average results of all the juices analysed, being 

 several thousand, obtained fi'om over one hundred distinct varieties 

 of sorghum, and for four successive years, so that the average results 

 can not but he accepted as of almost absolute accuracv. 



In 1879. the number of varieties under examination were but four, 

 and the number of analyses comparatively few, also the method for 

 the correct determination of specific gravity and composition of the 

 several juices not .so well established as in the later years, but as con- 

 firming the general fact that the specific gravities will enable one to 

 determine the composition of his juice, the results for 1879 are also 

 given. 



That such tables are of the greatest practical value to the manu- 

 facturer of sugar or ?yrup, is obvious. 



By reference to them, the sugar-boiler can determine quite accurately 

 the composition of any juice of which he knows the .specific gravity. Al- 

 thougli the varieties differ somewhat among themselves in the com- 

 position of the juice for the same specific gravity, .■^till these differences 

 are not so great as to be of much practical importance. 



In examining these tables, it should be remembered that the re- 

 sults are valuable in proportion to the uurnber of analyses from which, 

 each figure has been derived; therefore, while the figures derived from 

 a small number of analyses are true for the particular canes examined, 

 it is probable that a larger number of determinations would somewhat 

 modify the results. If only those figures are examined which are 

 based on ten or more analyses, it will be seen that the recorded results 

 are very seldom exceptional. 



Among other points shown by these tables, the following are im- 

 portant : 



1st. The amount of juice obtained seldom falls below 60 per cent 



