3 



These figures show a very healthy increase in the use of lime in Massachusetts 

 as a soil amendment. In 1928, the approximate tonnage sold in the state was 

 21,169, of which 13,166 tons was fine ground limestone. 



The present tonnage is about 85 per cent as great as that of commercial 

 fertilizer sold in the state. 



Explanation of Tables of Analyses. 



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

 this column are calculated from an actual determination of carbon dioxide (C0«). 

 Calcium or magnesium not in the form of carbonate is present either as hydrated 

 lime (water- or air-slaked) or as burned lime (caustic or unslaked). It should 

 be understood that 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 from the air. 



' ' Pounds of effective oxides in one ton " represents the sum of the calcium and 

 magnesium oxides in one ton of the lime product, assuming that both ingredients 

 from this source will become readily available. 



The calculations found in column "Cost of 100 pounds of effective oxides" 

 are based on prices furnished by the producers. 



Table II, "Pounds of effective oxides in one ton." In securing these data the 

 degree of fineness to which the limestone has been ground is taken into con- 

 sideration. On those products which are finely ground so that all of the material 

 will pass through a 20-mesh sieve, it is assumed that all of the calcium and mag- 

 nesium oxides will become available in the soil within a five-year period. On 

 those products which will not wholly pass a 20-mesh sieve, it is assumed that 

 the oxides in that portion which is coarser than 20-mesh will be only 50 per 

 cent effective during the same period. 



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

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



In both tables the figures in parenthesis following the brand name show the 

 number of samples collected and analyzed. 



