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tion was adopted which proved fallacious in 

 practice, and in consequence the farmer began 

 to doubt the truth of the new theory, and, labouring 

 under disappointment in his expectations, came to 

 view with distrust all other teachings of scientific 

 Agriculture. 



In very rare cases can we rely upon the figures 

 of a chemical analysis for gauging the capabilities 

 of a soil ; it is a test which can be turned to good 

 account only by the most initiated, and even then 

 great discrimination must be observed. Much light 

 has of late been thrown on this subject, and we 

 are beginning to understand more and more the 

 important role which the physical or mechanical 

 condition of the soil plays in connection with its 

 chemical composition. 



The constituents of the soil are in their original 

 form,asparts of rocks, insoluble in water ; they form 

 chemical combinations of a powerful nature, and are 

 hi this state incapable of serving as plant-food. 

 By the disintegrating action of moisture, heat, and 

 atmospheric air, the rock crumbles to pieces, the 

 pieces to powder ; the chemical combinations of 

 its constituents are severed, and the constituents 

 themselves become soluble in water. Corres- 

 ponding with this progress of disintegration, the 

 soil now acquires peculiar absorptive powers. For 

 if we allow water, containing a certain quantity of 

 each of the mineral constituents of plant -food in 



