TROPICAL PRODUCTS IN COMMERCE 53 



items, as will be noticed in the above table, vary in amount 

 imported from year to year according to the changes which 

 occur in the extension of manufacturing of various products. 

 Some articles imported from the Tropics appear to have 

 reached their maximum, at least with the present population, 

 and to be increasing slowly with the increase of population. 



The control and proper development of the Tropics is a 

 problem of tremendous consequences. Year by year more 

 tropical products become necessities in cold climates. This is 

 apparent from the mere casual consideration of a list of the 

 commonly imported tropical products, such as cane sugar, 

 coconuts, tea, coffee, cocoa, bananas, pineapples, citrus fruits, 

 olives, dates, figs, sisal, Manila hemp, jute, kapok, raffia, rub- 

 ber, balata, gutta-percha, chicle and other gums, cinchona, tans 

 and dyes, rice, sago, cassava, cinnamon, pepper, cloves, nut- 

 meg, vanilla, and other spices, oils, such as palm, China wood, 

 candlenut, castor, olive, cotton, lemon oil, etc. How many pub- 

 lic men in the United States are really giving attention to the 

 tropical question? Some energy has been expended in the 

 introduction and popularization of tropical fruits in order to 

 make our citizens familiar with these products and in order 

 to learn whether the fruits may be cultivated in southern Flor- 

 ida and California. This, however, cannot solve the whole 

 problem. It concerns merely one phase of the question, the 

 other and more important phase being the production of the 

 articles in question in tropical countries which are best suited 

 to the cultivation of such crops. 



The total land surface of the earth is estimated at 52,500,000 

 square miles. Of this area about 29,000,000 square miles is 

 considered as fertile land. The total land area of the Tropics 

 and subtropics is about 15,000,000 square miles. In the Trop- 

 ics it has been estimated by Willis that 50,000,000 acres are 

 devoted to the production of export crops and 275,000,000 

 acres to the maintenance of the inhabitants of tropical coun- 

 tries. This total of 325,000,000 acres cultivated in the Tropics 



