SUGAR 



949 



Palm- or Date-sugar. Many trees of the palm tribe yield a copious supply of sweet 

 juice, which, when boiled down, gives a dark-brown deliquescent, raw sugar, called in 

 India Jaggery. The wild date-palm and the gommuto-pulm yield the largest propor- 

 tion of this kind of sugar, which is chemically identical with the sugar from the cane, 

 though the crudeness of the manufacture is very injurious to it, and causes a largo 

 proportion to assume the uncrystallisable condition. One twenty-fourth of all the 

 cane-sugar extracted for useful purposes is obtained from the palm-tree. 



Beet-root Sugar. The extraction of sugar from beet-root, has become an important 

 manufacture in several countries on the. Continent, especially in France and German}-. 

 It was developed in consequence of the difficulty of obtaining colonial sugar in France 

 during the blockade in the time of Napoleon I. See BEET-ROOT. 



The proportion of sugar varies very much. The average proportion of sugar ex- 

 tracted from beet is 6 per cent., though it is stated that 7 per cent, is obtained in 

 some well-conducted manufactories. In France and Belgium the average yield is 14 

 or 15 tons of beet to the acre, while about Magdeburg they do not exceed 10 to 12 

 tons, but the latter are richer in sugar. 



During the first year of its life the root is developed to its full size, and secretes the 

 whole amount of sugar which, in the natural life of the plant, furnishes the material 

 for the growth and maturity of its upper part. 



The first manipulations to which the beets are exposed are intended to clear thorn 

 from the adhering earth and stones as well as the fibrous roots and portions of the 

 neck. The roots are washed by a rotatory movement upon a grating made like an 

 Archimedes' screw, formed round the axis of a squirrel-cage cylinder, -which is laid 

 horizontally beneath the surface of water in an oblong trough. It is turned rapidly 

 by means of a toothed wheel and pinion. The roots, after being sufficiently agitated 

 in the water, are tossed out by the rotation at the opposite end of the cylinder. 



The parenchyma of the beet is a spongy mass, whose cells are filled with juice. 

 The cellular tissue itself, which forms usually only a twentieth or twenty -fifth of the 

 whole weight, consists of ligneous fibre. Compression alone, however powerful, is 

 inadequate to force out all the liquor which this tissue contains. To effect this object, 

 the roots must? be subjected to the action of an instrument which will tear and open up 

 the greatest possible number of these cells. Experiments have, indeed, proved, that 

 by the most considerable pressure, not more than 40 or 50 per cent, in juice can be 

 obtained from the beet ; whilst the pulp procured by the action of a grater produces 

 from 75 to 80 per cent. 



The beet-root rasp is represented in figs. 1940, 1941. a, a is the framework of the 

 machine ; b, the feed-plate, made of cast iron, divided by a ridge into two parts ; c, 

 the hollow drum ; d, its shaft, upon either side of whose periphery nuts are screwed 



1940 



1941 



for securing the saw blades e, e, which are packed tight against each other by means 

 of laths of wood ; /is a pinion upon the shaft of the drum, into which the wheel g 

 works, and which is keyed upon the shaft h; i is the driving rigger ; k, pillar of 

 support ; /, blocks of wood, with which the workman pushes the beet-roots against 

 the revolving rasp ; m, the chest for receiving the beet-pap ; n, the wooden cover of the- 

 drum, lined with sheet iron. The drum should make 500 or 600 turns in the minute-. 

 By the process of M. Schiitzenbach the manufacture may bo carried on during the- 

 whole instead of during a few winter, months. At Waghausel, near Carlsruhe, this 



