CANE SUGAE. 



variety) varies within large limits; hence a ratio which may be quite satis- 

 factory in one factory will be totally inadequate in another. The writer has 

 frequently observed that when the White Transparent cane was being milled 

 in Demerara the megass accumulated, but the supply could not be burned fast 

 enough on the existing grate area to maintain the supply of steam. This 

 difficulty, which may become a great deal more serious than a mere incon- 

 venience, could in the writer's opinion be overcome by the installation of an 

 additional furnace wherein megass would be fired only when occasion arose. 



FIG. 223. 



If this difficulty is really due to differences in the weight of a cubic foot of 

 megass, its cure is surely to be found in increased grate area rather than in 



increased heating surface in the boilers. 



; _ ; 11 . ; ' . 1 ". .. 



Thermal Value of Megass. The combustible bodies present in 

 megass are fibre, sugar, glucose and details of other organic bodies ; the fibre 

 consists of cellulose proper, and xylan or wood gum. The heats of combustion 

 of these bodies as determined by Stohlmann and Langbein 3 are, cellulose, 7533 

 B.T.U., sugar, 7120 B.T.U., glucose, 6748 B.T.U. per Ib. Taking these heats 

 of combustion as a basis, and assuming that the fibre has the same fuel value 



410 



