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rapid is the growth of a crop and growth must be rapid if a 

 large produce is to be obtained the more liberal must be the 

 supply in the soil of phosphates, alkalies, and lime. Had 

 the turnips just referred to received superphosphate, we 

 should have expected larger crops of roots, and probably the 

 two kinds of dung would have shown more difference in their 

 effect on this crop. 



When everything has been done for thejand, we have still 

 the stern limitations imposed by the character of the season, 

 and especially by the supply of sunshine and rain throughout 

 the growing period. Any supply of plant food in excess 

 of the capabilities of the season is thrown away, a fact 

 to be continually borne in mind by those pursuing high 

 farming. 



After having applied the manures described during two 

 rotations without establishing any difference in their effect, a 

 change was made, and one-half of all the plots was cultivated 

 as before, but without any manure ; moreover, on this portion 

 of the field the whole of the roots (mangels) and the whole of 

 the clover was removed from the land. The object in view 

 was to see if by exhausting the land the crops would exhibit 

 any greater produce where the larger amount of nitrogenous 

 manure had been applied. The excess of nitrogen was due to 

 the consumption of about 1J ton of decorticated cotton-cake 

 in one case, and of 1J ton of maize-meal in the other case, 

 the difference between the quantities of nitrogen in these 

 foods being about 170 Ibs. per acre. The quantities mentioned 

 were distributed over the eight preceding years, the last 

 portion of the manure having been applied two or three 

 years before the commencement of the new unmanured 

 rotations. 



The first crops taken under the new system showed 

 perhaps a small excess on the cotton-cake plot. Where the 

 new system began with mangels, the first crops showed on an 

 average no excess on the cotton-cake plot ; where barley was 

 the first crop there was an excess of 1J bushel; where peas, 

 the excess was 4J bushels ; where wheat, If bushel. That 

 these small differences were really due to a residue of the 

 previous cakf manure must, however, be doubtful, as when 



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