PART VII 

 SOIL ANALYSIS 



Soil analysis leads to no such accurate valuation of a soil 

 as manure analysis does of a manure. Hence it is not a true 

 commercial analysis. An analyst is frequently asked to in- 

 vestigate a soil with a view to advising the farmer as to its 

 treatment. This is an exceedingly difficult problem, involving 

 as it does many conditions which cannot be determined in the 

 laboratory. Even in the laboratory the problem to be faced 

 by the chemist presents many difficulties. Perhaps this will be 

 best understood by reading the following excerpt from a paper 

 read before the Chemical Society by Dr. Bernard Dyer in 

 1894: 



' The chemical analysis of soils, which in the early days of 

 agricultural chemistry was looked upon as likely to be of 

 great practical use in agriculture, was soon found to be, as 

 ordinarily practised, of very limited value. Determinations in 

 the soil of the total quantities of the more important mineral 

 elements of plant food have been long recognised as affording 

 useful information only in exceptional cases ; and even in these 

 exceptional cases the results obtained have rather afforded 

 " probable indications " than absolute information. The 

 reason, as has often been pointed out, is that an analysis of 

 soil, as ordinarily made, shows the total percentage of its con- 

 stituents, or at any rate, the percentage dissolved by strong 



