12 THE PKINCIPLES OF 



The foregoing subjects do not by any means exhaust the 

 list which might be produced of excellent subjects for the 

 purpose of the teacher of agriculture. When he remembers 

 the varied processes of the dairy, the many considerations 

 with reference to the management of breeding animals, rear- 

 ing and fattening, as well as of crop cultivation generally, he 

 need not bs afraid of running short of a subject, neither need 

 he be thrown exclusively upon such topics as the action of 

 lime upon organic matter, the formation of double silicates 

 in the soil, the change from dormant constituents into active 

 or soluble ingredients in the soil; and while inculcating topics 

 similar to those above enumerated, he will be more truly 

 teaching agriculture and promulgating information which is 

 known to be important to those persons whose lives are being 

 devoted to the pursuit of agriculture. In treating of this 

 subject upon the wider basis which I am endeavouring to 

 lay down, I would recommend that attention should in the 

 first place be devoted to the soil, and that in as broad a 

 manner as is possible. The origin of the soil, the distribution 

 of the soil in accordance with the outcrop of the various 

 geological strata, the conditions of fertility in soils, including 

 climate, subsoil, texture, aspect, as well as mere available 

 plant food, and the possible occurrence of injurious matters 

 which may interfere with what otherwise would have been 

 a fertile soil. The indications of fertility offer a most 

 interesting inquiry for the agricultural teacher which appears 

 to be entirely unexplored and unappreciated by those who 

 profess this subject. These indications appeal to the five 

 senses, and ought to include the consideration of the geo- 

 logical position of the soil in question, contour, altitude, 

 shelter, depth, colour, tenacity, subsoil, as well as the natural 

 produce, as illustrated in the trees, "hedgerows, permanent 

 pasturage, weeds, and growing crops. Botany here comes in 

 as the handmaid of agriculture, for certain trees and certain 



