718 GRAMINE^. 



Barbados,^ and Jamaica,^ produce at present the largest quantity of 

 sugar. 



Production — No crystals are found in the parenchyme of the cane, 

 the sugar existing as an aqueous solution, chiefly within the cells of the 

 centre of the stem. The transverse section of the cane exhibits numerous 

 fibro-vascular bundles, scattered through the tissue, as in other monoco- 

 tyledonous stems; yet these bundles are most abundant towards the 

 exterior, where they form a dense ring covered with a thin epidermis, 

 which is very hard by reason of the silica which is deposited in it.^ In 

 the centre of the stem the vascular bundles are few in number ; the 

 parenchyme is far more abundant, and contains in its thin- walled cells 

 an almost clear solution of sugar, with a few small starch granules and 

 a little soluble albuminous matter. This last is met with in larger 

 quantity in the cambial portion of the vascular bundles. Pectic piin- 

 ciples are combined with the walls of the medullary cells, which how- 

 ever do not swell much in water (Wiesner). 



From these glances at the microscopical structure of the cane, the 

 process to be followed for obtaining the largest possible quantity of 

 sugar becomes evident. This would consist in simply macerating thin 

 slices of the cane in water, which would at once penetrate the paren- 

 chyme loaded with sugar, without much attacking the fibro-vascular 

 bundles containing more of albuminous than of saccharine matter. By 

 this method, the epidermal layer of the cane would not become saturated 

 with sugar, nor would it impede its extraction, — results which necessarily 

 follow when the cane is crushed and pressed.* 



The process hitherto generally practised in the colonies, — that of 

 extracting the juice of the cane by crushing and pressing, — has been 

 elaborately described and criticised by Dr. leery of Mauritius.^ In that 

 island, the cane, six varieties of which are cultivated, is when mature 

 composed of Cellulose, 8 to 12 per cent. ; Sugar, 18 to 21 ; Water, includ- 

 ing albuminous matter and salts, 67 to 73. Of the entire quantity of 

 juice in the cane, from 70 to 84 per cent, is extracted for evaporation, 

 and yields in a crystalline state about three-fifths of the sugar which 

 the cane originally contained. This juice, called in French vesou, has on 

 an average the following composition : — 



Albuminous matters ... ... ... ... 0'03 



Granular matter (starch ?) . . . ... ... ... O'lO 



Mucilage containing nitrogen ... ... ... 0'22 



Salts, mostly of organic acids® ... ... ... 0*29 



Sugar 18-36 



Water 8100 



iOO-00 



^ 38,013 hhds. in 1876. " means of cold water from the sHceil and 



^ 29,074 hhds. in 1876. dried cane, seem to promise good results. — 



^ Stems of American sugar cane, dried at See a paper by Dr. H. S. Mitchell in Journ. 



100° C, yielded 4 per cent of ash, nearly of Soc. of Arts, Oct. 23, 1868. 



half of which was silica. — Popp, in Wiggers' '^Annates de Chimie et de Physique, v. 



Jahreshericht, 1870. 35. (1865) 350-410.— See also, for Cuba, Alvaro 



* The plan of obtaining a syrup by mace- Reynoso Ensayo sabre el cuUivo de la cafla 



rating the sliced fresh cane, has been tried de Azucar, Madrid, 1865. 359. — For British 



in Guadaloupe, but abandoned owing to Guiana, Catal. of Contribtdions from Biit. 



some practical difficulties in exhausting the Guiana to Paris Exldb. 1867.pp. xxxviii. -xli. 



cane and in carrying on the evaporation of ^ Aconitic Add (p. 11) has been met 



the liquors with sufficient rapidity. Ex- with by Behr (1877) in West Indian 



periments for extracting a pure syrup by molasses. 



