The Neglect of Cliewistrij hij Practical Farmers^. 



443 



means of a similar analysis of their own soils farmers may judge 

 how far any ingredient may be dispensed with in the manure, on 

 account of its abundance in the soil, and vice versa. 



The practical correctness of this result, obtained from theoretical 

 deductions, has been curiously verified by a report, published 

 since this was written, on the system followed by Mr. Hudson, of 

 Castle Acre, who imports annually upwards of 200 tons of oil- 

 cake, in addition to special manures for all his turnips, on an 

 arable farm of 1200 acres. 



There is one slight error in this table, and that is, I have 

 omitted to deduct the amount of seed sown from the produce of 

 the crop, the balance only being the real loss that the land has 

 sustained. 



It is of no importance as regards a hypothetical case, but when 

 calculating the amount for actual crops, this item must not be 

 forgotten. 



The intelligent reader will no doubt be able to ask himself and 

 answer many other questions of a similar nature which may occur 

 to him, without the assistance of further examples, such as the 

 different exhausting powers of various rotations, the difference to 

 the succeeding crop by pulling or feeding off a crop of turnips, 

 the money value of any manure to the farmer, calculated from the 

 market value of its constituents, &c. In fact, the questions of 

 interest that these tables will, it is hoped, throw some light upon 

 are so numerous, that it would require almost as many tables as 

 are already contained in this work to illustrate each one by an 

 example. 



General Reviarlis. — In consulting the tables, the reader must 

 not be surprised at finding that the aggregate weight of the 

 individual ingredients sometimes exceeds the given amount of 

 ash, and in other cases falls short of it ; this arises from my 

 having adopted the rule, now almost uniformly followed by 

 scientific writers, of giving the actual amount of each ingredient, 

 as found in the analysis, and referring the defi.cit or overplus to 

 loss or gain incurred during the operation of analysis, instead of 

 doctoring the results, by dividing the loss or overplus, as the 

 case may be, amongst the various ingredients, and thereby giving 

 a fallacious appearance of accuracy to the tables. The amount 

 of loss or gain in any instance may be taken as a measure of the 

 general accuracy of the analysis. 



In conclusion, I may state that in apportioning the space to 

 each subject I w^as actuated only by wdiat I considered their 

 relative importance to the farmer, and not by the number of 

 analyses obtainable of any individual specimen, and in all cases 

 my object has been to compare the results obtained by different 



