RIGHT USE OF LIME IN SOIL IMPROVEMENT 



appreciable difference in price in favor of 

 air-slaked lime, as compared with a fine 

 stone. 



Air-Slaking a Slow Process. Lime 

 changes to an air-slaked condition slowly 

 unless it has full exposure. Old heaps will 

 remain in hydrate form for many years, ex- 

 cepting the outside coat, which excludes the 

 air. Complete air-slaking would not re- 

 duce ability to correct soil acidity, the total 

 amount of calcium and magnesium remain- 

 ing constant, but weight would be added in 

 the slaking, and therefore the value per ton 

 would be reduced. The slowness with 

 which air-slaking proceeds gives reason to 

 expect that any bulk of old lime may con- 

 tain a considerable percentage of the hy- 

 drate, and therefore have greater strength 

 than a true carbonate like limestone. This 

 is a consideration of value to a buyer. 



Agricultural Lime. Some manufac- 

 turers have found in the demand for lime 

 by farmers an opportunity of disposing of 

 much material that would not be satisfac- 

 tory to manufacturers and builders. In 

 some cases this so-called agricultural lime 

 is sold at a price that is not beyond value, 

 but it varies much in its content of pure 



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