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determined by the mode of culture, &c, with which the 

 superior crops were obtained. Of two farms having the 

 same soils, and equally luxuriant crops, — the one raised by 

 oil cake, manure, and bones, — the other by rape dust, guano, 

 nitrate of soda, or by artificial manures, — the farm got into 

 condition by the former is of much greater intrinsic value, and 

 will be cultivated at less expense for the future, than a similar 

 farm producing equally good crops obtained by artificial 

 manures. By not attending to this point, we neither know 

 the maximum producing point of any particular soils, nor the 

 lowest rate at which any particular crop may be produced. 

 Again, upon the shallow sandy soils, as well as upon the 

 clayey soils in Yorkshire, there are this year above average 

 crops, which might for the time being mislead the judg- 

 ment respecting their value. The value of permanent grass 

 land is also liable to be mistaken. There are innumerable 

 instances of grass fields, upon naturally superior soils, having 

 become greatly deteriorated in their produce by bad manage- 

 ment, and which, to judge from the vegetation, would be 

 pronounced inferior land ; yet these swarths, if ploughed up, 

 will produce excellent crops of grain and artificial grasses. 

 Again, upon the Chalk Wolds and the Magnesian Limestone, 

 only very small portions, (those which contain less than five 

 per cent, of alumina,) produce good crops of grass ; so that 

 upon these formations, land of fair or average quality might be 

 condemned on account of the inferior grass land contiguous 

 to it. The vegetation, however, afi'ords other signs, which 

 may with confidence be relied upon ; as the timber growing 

 in the hedge-rows, whether it be full grown or stunted — of 

 what species — if covered with moss or lichen — if leaning in 

 one direction ; likewise the weeds and plants growing in the 

 fields and hedges, as well as those in the lanes and roads 

 adjoining the land, have their value as criteria. 



These three signs, viz., colour, consistence, and vegetation, 



