CROPS TO SOILS. 185 



sand over clay. These lack carbonate of lime, and humus 

 and clay ; and clay-marl or blue clay, or indeed any clay, 

 properly applied, would constitute an excellent dressing 

 for them. Green crops, of any sort, turned under with 

 the plough, are here particularly serviceable. When 

 duly enriched they will bear good rye. Clover, or other 

 green crops, should frequently intervene in the alterna- 

 tion. If dry, sheep may be advantageously pastured 

 upon them. 



We will here make some suggestions as to the mode 

 of applying marl or clay to sandy lands, though at the risk 

 of repeating what we may have already said upon this 

 subject. The object of the apphcation is to improve the 

 absorbent and retentive properties of the soil, as it regards 

 moisture and manure. It is hence important that the 

 clay or marl should be pulverized and intimately incor- 

 porated with the soil. Pulverization can only be effect- 

 ed by exposing the marl or clay to the action of the frosts, 

 rains, and the sun. If laid upon the ground in masses, 

 or heaps, pulverization is but partially effected, and that 

 only upon the surface of the heaps. It is advisable there- 

 fore, and it is the practice we have settled upon, to draw 

 the clay or marl on to the ground in autumn or winter, 

 and to spread from the carts, as far as its adhesive quali- 

 ty will permit, over the entire surface of the field. The 

 lumps become saturated with rain, the frosts penetrate, 

 expand their volume, and loosen their adhesive proper- 

 ties, and when the clay or marl afterwards becomes dry, 

 they may be broken down by a maul, and pretty well 

 pulverized and distributed by the roller and harrow. The 

 operations of tillage will then produce as good a mix- 

 ture as can be expected. Were the attempt made to 

 blend these materials with the soil, without the prepara- 

 tory process of pulverization, much of the benefit of the 

 application would be lost. Besides, the clay and marl, 

 by exposure to atmospheric influence, part with deleteri- 

 ous properties which they often possess when drawn from 

 the pit, and are ameliorated and enriched by the atmo- 

 sphere. Judging from experience, we consider twenty 

 or thirty-two horse loads of blue clay, containing, like that 

 16* 



