AGRICULTURE. 135 



rainfall altogether different in quantity and distribution — 

 and reaped abundantly under the combination of circum- 

 stances presented to him in those countries, certainly can 

 have no just ground for assuming that these countries 

 are unsuited for agriculture because the like cannot be 

 done here. On equal grounds, the farmer who sows and 

 reaps maize here, might assume that Scotland was unfit 

 for husbandry because maize will not ripen there I Yet, 

 from such data as this have conclusions been drawn. 



Every few degrees of latitude, every few hundred feet 

 of elevation, marks a difference of agricultural products, 

 and determines the more or less favourable conditions of 

 their culture. 



There are certain laws which govern these things. 

 These laws are universal, but their appUcation (as de- 

 monstrated by those same laws) is various — infinitely 

 various. The science of Agriculture is the embodiment 

 of these laws, and their just application. 



The possession of a rich soil by any country marks it 

 infaUibly as suitable for agriculture ; as the very existence 

 of a rich loamy soil, presupposes, and is the result of, a 

 prior rich vegetation. The science of Agriculture teaches 

 how this can be made available for reproduction in 

 higher classes. The laws of tillage and its effects are 

 everywhere the same ; each plant, however, requires 

 special conditions for its full development, and the busi- 

 ness of the agriculturist is to select the plants for culti- 

 vation suitable to the conditions at his command ; or by 

 his art provide artificial conditions, or modify existing 

 ones. When moisture is deficient, irrigate ; when in 

 excess, drain; when the food elements of plants are 

 wanting, supply them to the soil ; if land is cold, raise its 

 temperature by breaking it up to a considerable depth, 

 and thereby elevate the surface, subdividing its substance 



