follows that no progression at all should be made: the 

 elements of growth may be supplied; but the application 

 of them should be guided by moderation, being lessened 

 at those particular periods when the weather is least 

 propitious, and increased during those periods when it 

 is most favourable. In the works of Nature we may ever 

 learn a lesson of consistency, for they are perfect : they 

 teach us that food is requisite to maintain the life of all 

 those objects which are endowed with it ; that that food 

 must undergo a process both of digestion and assimila- 

 tion, ere its purpose is fulfilled ; and that each of these 

 processes depend on the action of natural agents. In 

 the vegetable kingdom, heat and light as derived from a 

 united source, are the agents appointed to bring about 

 these results, and in order to ensure their proper action, 

 they must both be present in a powerful degree: in 

 artificial schemes of culture, we can command a supply of 

 the one, but the other is not within our power ; our con- 

 sistency therefore depends on our applying so much of 

 the one under our controul, as will secure the united 

 action of it, with the existing degree of the other con- 

 sequently, when light is absent, or deficient, heat should 

 also be diminished; and when light is present and abun- 

 dant, heat may safely be increased. 



D 



