WHAT SHALL ONE BUY? 



limestone. It is a lime carbonate, and the 

 percentage of worthless material in it varies 

 somewhat. It is coarsely ground, but the 

 large pieces disintegrate in the soil much 

 more rapidly than limestone would do. It 

 contains a little nitrogen and phosphoric 

 acid, partially available, as an offset to 

 coarseness and some lack of purity, as com- 

 pared with the highest grade of fine stone. 

 It is profitable to buy oyster shell at lime- 

 stone prices if used liberally enough to fur- 

 nish a supply for a term of years. The 

 oxide, or burned shell lime, would be nearly 

 the equivalent of burned stone if it did not 

 change to hydrate and air-slaked forms so 

 rapidly that it rarely is on the market in the 

 full strength of fresh burned lime. 



Hardwood Ashes. As a source of lime, 

 ashes have become far too expensive. The 

 composition of ashes on the market is widely 

 variable, dirt and moisture often accounting 

 for much of the weight. The lime in fresh 

 burned ashes is peculiarly effective, being 

 finely divided and in oxide form, but the 

 ashes on the market have much of the lime 

 water-slaked and air-slaked. Unless analy- 

 sis is made at time of purchase, a buyer 

 should not estimate the content of lime in a 



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