Proceedhstgs of Seventeenth ^N'ormal Institttte 137 



These results were secured iu the following manner : Four treat- 

 ments of burnt lime, each of 8 tons per acre, and four treatments 

 of slaked lime in exact chemical neutralizing equivalence to 

 finely-divided, chemically-pure CaCOs, or precipitated chalk, 

 were applied to an acid loam soil inclosed in metal cylinders in the 

 field. The chemically-pure, fine carbonate checks were included 

 to insure greater fairness of comparison with reference to in- 

 fluence of fineness upon chemical reaction. With these treatments 

 were also made eight applications of ground limestone, the rela- 

 tionship of which to the fine carbonate we will later see. Each 

 application was mixed with soil to a depth of G inches, being 

 thoroughly incorporated in order to permit of soil sampling for 

 chemical analysis. Periodic examinations of the oxide and hy- 

 drate treatments were made, once each week for eight weeks. 

 During the first six weeks we found an increase of carbonate from 

 CaO and Ca(0H)2, there being, however, no further appreciable 

 increase of carbonates during the seventh and eighth weeks. 



The data show practically complete carbonation of the applied 

 burnt and hydrated lime. A vast array of data, which it is not 

 necessary to give here, has further shown that where we apply 

 burnt lime and leave it upon the surface, it will be more quickly 

 carbonated than it could be if it were incorporated in the soil. 

 Now suppose we were to apply burnt lime to a dry soil mulch; 

 the burnt lime could not combine with the dry mulch, but it 

 could and would be carbonated. We then have the carbonation 

 of applied lime before its admixture in and reaction with the 

 soil. It is apparent, then, that instead of incorporating burnt 

 lime into the soil we are, in fact, making a treatment of calcium 

 carbonate in its finest possible form. But, suppose we have con- 

 siderable rain immediately after we apply our lime. We then have 

 a movement of lime, partly as lime water and partly as carbonate 

 in solution of carbonated water, down into the soil ; where, under 

 some conditions, part will react with the soil and be fixed, while 

 under other conditions part will be leached away. ISTow in case of 

 the amounts of lime ordinarily used in practice — say two tons 

 — whether the lime be first completely carbonated or not, with the 

 occurrence of sufficient soil moisture we have but a small fraction 

 of the applied lime, if any, remaining long in the soil as carbonate. 



