overrun in tlie other ingredient (calcium or magnesium according to the de- 

 ficiency) so that there was no decrease in neutraUzing value. The exception was 

 Monarque Agricultural Dolomite, manufactured by Clifford L. Miller. This 

 product was found deficient .91 per cent in calcium oxide and .74 per cent in 

 magnesium oxide, or a net deficiency of 1.94 per cent in calcium oxide equivalent. 

 Several of the unburned lime products should be more finely ground to become 

 as elTective as is the hydiated product when used in amounts to furnish the 

 equivalent of calcium and magnesium oxides. The following products would be 

 more effective in neutralizing soil acidity if more finely ground. The finei' grind- 

 ing of unburned lime products means a greater surface exposed to chemical action 

 in the soil, with a corresponding increase in availability. 



Magnesium Limestone, American Agricultural Chemical Co. 



Ground Limestone, Hazen Brothers. 



Hoosac Agricultural Limestone, Hoosac Valley Lime Co., Inc. 



Monarque Agricultural Dolomite, Clifford L. Miller. 



Monarque Agricultural Limestone, Clifford L. Miller. 



Sealshipt Oyster Shell Lime, Producers Sales Co. 



Ashley White Dolomite Agricultural Limestone, D. U. Smith & Brother. 



Solvay Pulverized Limestone, Solvay Process Co. 



What has been said with reference to deficiencies in the unburned lime products 

 applies also to the hydrated limes. Although calcium oxide deficiencies were 

 noted in seven brands, yet all of these were accompanied by sufficient overruns 

 in magnesium oxide so that the net value of the products was not impaired. 

 One brand, Gibsonburg Hi Lime, manufactured by Gibsonburg Lime Products 

 Co., showed a deficiency of .69 per cent calcium oxide and .52 per cent magnesium 

 oxide or a net deficiency of 1.55 per cent in calcium oxide equivalent. 



Explanation of Tables of Analyses 



Table 1, "Proportion of total oxides as carbonates." The data furnished in 

 this column are calculated from an actual determination of carbon dioxide 

 (COj^ Calcium or magnesium not in the form of carbonate is present either 

 as hydrated lime (water- or air-slaked), burned lime (caustic or unslaked), or 

 as basic silicate. All of the products listed in this table have at some time been 

 burned, and the proportion of oxides present as carbonates indicates to what 

 extent the product has absorbed carbonic acid fiom the air. 



Table II, "Carbonates of calcium and magnesium." The calculation in this 

 column allows for the small amounts of calcium and magnesium combined 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 

 percentage of product that would pass the various meshed sieves mentioned. 



Tables 1 and II. "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 has been added. 



The figures in parenthesis following the brand name show the number of 

 samples collected and analyzed. 



