FERTILIZERS AND AGRICULTURAL LIME 43 



Explanation of Tables of Analyses 



Tables I, II, III, "Neutralizing value expressed in terms of calcium oxide" 

 represents the acid neutralizing value of both the magnesium and the calcium. 

 The figures in the "per cent" column are obtained by a direct titration with 

 standard acid. The "pounds in one ton" are secured by multiplying the figures 

 in the "per cent" column by 20. 



"Insoluble matter" represents material which is insoluble in dilute hydro- 

 chloric acid to which a few drops of nitric acid have been added, and is mainly 

 sand. 



Tables II and III, "Carbonates of calcium and magnesium". The figures in 

 this column are exclusive of the small amounts of calcium and magnesium com- 

 bined as basic silicates; these are readily soluble in mineral acid solutions but 

 obviously should not be classed as carbonates. 



Under "Mechanical analysis" the figures represent in round numbers the per- 

 centage of product that would pass or be retained by the meshed sieves men- 

 tioned. 



The limestone products have been published in two groups or grades (see 

 tables II and III) according to fineness of grinding and to conform to definitions 

 voted by the Association of Official Agricultural Chemists at their 1936 meeting. 



