STARCH-PRODUCING PLANTS. 339 



12. Plantain 16'99 



13. Sweet potato 16-31 



14. Buck yam 16'07 



15. Another sample 15'63 



16. A third, from a dark colored variety 14'83 



From the foregoing list it appears that the sweet and bitter 

 cassava merit attention as starch-producing plants. They are 

 occasionally grown for this purpose in the colonies, and yield a large 

 per centage of starch ; but there exists an opinion, whether well 

 or ill founded, that it is liable to rot linen, and the preference is 

 given here to the starch of arrowroot. It remains to be seen, 

 however, what estimate will be formed of this starch in England, 

 for if it should prove an esteemed variety, there can be no doubt 

 of its proving a highly profitable cultivation. Cassava grows 

 readily in. almost any soil, and when the drainage is tolerable, two 

 crops of the sweet variety can, it is stated be grown in a year. I 

 have seen it growing luxuriantly in the light soils of the interior, 

 as well as in the stiff clay soils of the coasts. It is considered an 

 excellent preparatory crop in new and stiff land, on account of its 

 tendency to loosen the soil. Were the bitter variety fixed 011, the 

 preparation of Casareep might be combined with the preparation 

 of starch ; and as that substance is one of the most esteemed 

 bases for the preparation of various sauces, it is probable that this 

 might turn out the most profitable part of the produce. At all 

 events, bitter cassava would have this advantage over all other 

 starch-producing roots, that the juice of the roots could be turned 

 to account as well as the starch. 



Of all the plants mentioned in the list, starch is most readily- 

 separated from the arrowroot, in consequence of the tissue being 

 more fibrous, and yielding little or no cellular tissue requiring to 

 be run off the starch. Time and water are thus saved in the 

 process, and were the fibrous residue pressed and dried, it could 

 probably be turned to good account in the manufacture of paper. 



In respect of facility of preparation, the plantain starch, though 

 of excellent quality, ranks lowest, for the flesh-colored tissue in 

 which the starch is embedded is somewhat denser than the starch, 

 and settles down under it, and it is not a little difficult to arrange 

 the process so as completely to separate the finer parts of this 

 matter from the starch, and hence its color is never perfectly 

 white. 



Yield of starch-producing plants per acre. On this subject, as 

 already remarked, I do not at present possess sufficiently accurate 

 data. 



In England ten tons of potatoes are not unfrequently produced 

 per acre; now assuming 15 the per centage of starch, there 

 would be a yield of one-and-a-half tons per acre, which, at the 

 lowest quotation, 28s. a cwt., would give 42 per acre; and 

 were the starch to rank with that prepared from wheat, it 

 would produce 40 per ton, or 80 per acre. In the thorough 

 drained land of Demerara, and under a good system of cultiva- 



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