CHAPTER II 

 THE COMPOSITION OF THE SUGAR CANE 



IN writing of the composition of the cane, distinction must be made between 

 the stalks and the whole plant, including therein the leaves, tops and 

 underground system. The composition of the former is of major interest 

 to the manufacturer, while the agriculturist is more concerned with the 

 composition of the whole crop. 



Distribution of the Crop as between Stalks and Leaves. A very complete 

 account of the distribution of the crop as between stalks on the one hand 

 and tops, leaves, and dead cane on the other, was made by Maxwell 1 in 

 Hawaii in connection with a number of varieties. Excluding certain 

 abnormal figures, the dry matter in the stalks amounted to 45 per cent, 

 of the entire crop, the leaves, etc., accounting for 55 per cent. This analysis 

 of the crop did not take into consideration the root system, which Kobus 

 has estimated at two to three tons of dry matter per acre, whereby the pro- 

 portion of dry matter in the stalks would be reduced to the neighbourhood 

 of 40 per cent, of the entire product. 



Composition of Different Parts of the Cane.-^Analyses due to Agee and 

 Halligan 2 of Louisiana cane gave the results below : 



STALKS ROOTS SEEDS LEAVES 



per cent, per cent, per cent, per cent. 



Water .. .. .. 74*96 68-79 11*03 74*38 



Ash .. .. ., 0-64 1-87 5- 22 2-23 



Fat and Wax .. .. 0-38 0-54 2-01 0-69 



Nitrogenous bodies .. 0*58 i*59 8*47 1*70 



! Crude cellulose 4-86 9*58 25*51 9*i8 



Pentosans .. 3'4 7*4 26-26 5*49 



Ligneous bodies 2-14 4-25 21-50 4-13 



Sugars, etc. .. .. 13*4 6-34 2-20 



Combining these results with those quoted in the preceding section, it is 

 easy to see that the very great part of the material removed from the soil 

 is contained in that part of the crop which remains on the land. 



The Quantity of Sugar in the Cane Stalks. The sugar in the stalks varies 

 between very wide limits and is affected by variety and by conditions of 

 growth. The earliest analyses made were those of Casaseca 3 in Cuba, 

 and the classical analysis is that due to Payen, 4 who, working on material 

 sent to France from the West Indies, and in the absence of a polariscope, 

 found the percentage of sugar to be 18. Other early French workers obtained 

 similar results, the maximum recorded being 26 per cent. It is unfortunate 



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