240 Coffee Planting. 



improved, to a certain extent, by the application of 

 manure, but as this is a process involving more or 

 less labour and expense, it is obvious that those 

 which are originally the most fertile are the most 

 economical to the cultivator. Moreover, soil which 

 is naturally rich will always be more productive and 

 lasting, than that which has had to be made fertile 

 by artificial means. 



Another object of manuring is to restore to 

 plants, through the soil, those particular con- 

 stituents which have been unduly wasted by a 

 preternatural fruitfulness, induced by artificial cul- 

 ture, and in consequence of which the plants are 

 threatened with premature decay. 



The chemical constituents of plants are hy- 

 drogen, oxygen, nitrogen, and carbon, and some 

 few earthy salts ; and, therefore, bodies containing 

 these elements, arranged in a manner suitable for 

 absorption by the roots of plants, are those best 

 adapted for use as manure. Decaying animal and 

 vegetable matter, and a few mineral substances, 

 answer this description, and consequently make up 

 the various manures used in cultivation ; and the 

 more fluid and gaseous the nutritious parts of these 

 are, the more easy of absorption will they be. Mr/ 

 Rhind, in his " History of the Vegetable Kingdom/ 1 

 says, "The great object in the application of 

 manure should be to make it afford as much 



