HARDWICKE'S SCIENCE-GOSSIP. 



§5 



cultivated throughout all tropical countries for the 

 sake of the starchy root, which in various forms 

 constitutes a very important article of diet. 



It is a small shrubby plant, growing from four to 

 eight feet high. Root large, tuberous, oblong, fleshy 

 and white, abounding in a milky, acrid, resinous juice, 

 sometimes weighing as much as thirty pounds. Leaves 

 palmately-partite, with from five to seven lanceolate 

 acute divisions, smooth, glossy, glaucous beneath. 

 Flowers in axillary racemes, monoecious. The root 

 is usually collected when weighing about six or eight 

 pounds, as the older it gets the greater is the amount 

 •of woody fibre developed ; this size is acquired under 



Fig. 38. — Branch of Piper metkysticum (reduced) 



good cultivation in about nine months after the young 

 plants are established ; although in some instances 

 they are allowed to stand for sixteen or eighteen 

 months. 



As I have intimated above, the root abounds in a 

 peculiar poisonous juice, which is stated to be analo- 

 gous] to hydrocyanic acid, and yet in combination 

 with such a virulent substance a most wholesome 

 food exists, and is obtained free from it ; this is due 

 to the volatility of the principle, and the facility with 

 which it is destroyed by fermentation, while if any 

 remain after this process is undergone, it is easily 

 expelled by heat when the crude material is subjected 



to roasting. The old method of manipulation is as 

 follows, and this is still largely practised now, although 

 enterprising firms have called in the aid of the en- 

 gineer, the result being that suitable machinery now 

 exists in many districts, which is not only a great 

 labour-saver, but the starch is more effectively and 

 quickly removed, and a better sample is secured. 

 After the roots are dug up, they are peeled and made 

 into a pulp, and thoroughly washed in cold water, 

 and when at rest the starch subsides, after which the 

 water is drawn off, and the starch is heated on hot 

 plants ; the pearl tapioca being granulated. To 

 obtain the cassava meal the roots are cleaned, grated, 

 pressed, dried, sifted, and then 

 slightly baked on an iron plate ; 

 thus prepared it swells considerably 

 in water or broth, and is called 

 " conaque." If, instead of drying 

 the grated pulp, it is spread upon 

 a hot iron plate, the starch and 

 mucilage, by mixing together, con- 

 solidate the pulp and form a biscuit 

 called cassava-bread, which is a 

 very important and nutritious food, 

 and is sold at a very cheap rate. 

 These cakes are also masticated in 

 the same way as the kava root, by 

 the women, and ejected into large 

 bowls, where it is allowed to fer- 

 ment for some days, after which it 

 is boiled and clarified, when it con- 

 stitutes a very agreeable, but intoxi- 

 cating, drink. 



The following remarks upon the 

 improved method of manipulation 

 by machinery are taken from the 

 "Gardener's Chronicle," June 17th, 

 1882, where other details are given 

 respecting the cultivation of the 

 plant in the Straits Settlements. 

 "The roots being first divested of 

 their woody tops, are thrown into 

 a large revolving drum, in which 

 pipes are so arranged that jets of 

 water play on them as they are turned 

 over and over, and gradually they 

 reach the farther end of the drum perfectly clean, and 

 empty themselves into a rasping machine, whence they 

 emerge in the form of fine pulp, which is thrown 

 direct from the rasper into another cylinder covered 

 either with stout muslin or brass-wire gauze, through 

 the sides of which jets of water are continually passing. 

 By this process the starch is separated from the pulp, 

 the starch passing through the muslin or gauze into a 

 tank beneath, where further supplies of water send it 

 through gutters to vats prepared for its reception, 

 while the pulp is discharged from the drum into 

 baskets and thrown into heaps, either for cattle 

 feeding or manure. After the starch in the vats has 



