332 STABCH-PRODUCTNG PLANTS. 



indeed of nearly allied crops ; and although fewer valid objections 

 can be urged against the continued cultivation of the sugar cane, 

 when properly conducted, than against that of grain crops, it is 

 nevertheless certain that a well-arranged alternation or rotation of 

 crops would be better. "When an efficient system of covered 

 drainage is adopted in British Guiana, there can be no doubt that 

 the sugar cane will be replanted at shorter intervals of time than 

 at present, and that other crops, such as provender crops for cattle, 

 and provision crops for the colonial and perhaps the home market, 

 will be made to alternate in cultivation with the cane. When the 

 cane rows are as far apart as they require to be, to admit of suf- 

 ficient tillage with the plough and other implements, it will also be 

 possible to intercalate crops of rapidly growing plants ; and were 

 this done, as it easily might, in such a manner as to prevent undue 

 exhaustion of the land, or impoverishment of the sugar crop, the 

 returns could not fail to be materially increased. It would then 

 probably be found that the fluctuations in prices would be less 

 felt, for they would not likely, at the same time, affect different 

 crops in the same manner. 



It has been ascertained, in regard to some plants at least, that a 

 much larger return can be obtained in the colonies than can be 

 grown in temperate countries, however fertile. This is partly 

 owing to the greater fertility of the soil under powerful tropical 

 atmospheric influences, and partly to the fact that vegetation is 

 continuous throughout the year, so that slow growing plants can 

 do more within the time, from their functions not being arrested 

 by the chill of winter ; and of many rapidly growing plants, two 

 successive crops can be grown within the year. 



Starch is a substance easily manufactured, and being largely 

 used in several of the arts, as well as an article of diet, there con- 

 sequently exists a considerable demand for it in England. It may be 

 obtained from a great variety of plauts, and many of the most 

 productive of it are natives of the tropics. 



The high prices commanded by grain and bread-stuffs in Europe, 

 renders the present a remarkaoly favorable time to ascertain what 

 can be done in this branch of tropical agriculture ; for should the 

 potato disease return, or this root be less extensively planted than 

 hitherto, starch must maintain a high price, and it will be worth 

 ascertaining whether some of the superior starch-producing plants 

 of the tropics might not be cultivated to such an extent as to 

 supply the English market, and thus be at once profitable to the 

 colonies and advantageous to the mother country. 



Before entering on such a cultivation, however, various points 

 require investigation. "We ought to be able to answer such ques- 

 tions as the following : 



1. What differences exist between the characters of starch pro- 

 duced by different plants ? 



2. What are the qualities or properties that lead manufac- 

 turers calico printers for example to prefer one variety to 

 another ? 



