806 LIMING. 



doninff, at the same time, its constitutional water, by which, in due 

 season, the hydrate of lime becomes changed into the anhydrous 

 carbonate of lime. This process is always slow ; more rapid at 

 first, when the interchange between the carbonic acid and watei 

 takes place freely ; it becomes gradually slower and slower as there 

 is less and less water left in the particles : the affinity of the lime 

 for the water seems to increase continually in the ratio of the small- 

 ness of the quantity which it still contains. It must, therefore, con 

 stantly happen that in incorporating lime, in powder and partially 

 carbonated with the soil, we also introduce lime that has preserved 

 its causticity in some measure ; it must be observed, however, that, 

 once intimately mixed with the soil, this lime must speedily pass 

 into the state of carbonate, because the soil and the water with which 

 it is moistened always contain a considerable quantity of carbonic 

 acid. Though we commence operations with quick-lime, conse- 

 quently, it is carbonate of lime that is definitively introduced into the 

 ground. 1 have thought this a point of sufficient importance to en- 

 gage our attention for a short time, inasmuch as it simplifies the 

 view of the end that is to be sought in applying lime; this, as M. 

 Puvis has most satisfactorily established, is neither more nor less 

 than the introduction into the ground of that proportion of the calca- 

 reous element which it either wanted originally, or which it has lost 

 in the course of repeated cropping, in order to enable it to produce 

 abundantly. Quick-lime incorporated with the soil must pass, as I 

 have shown, very rapidly into the state of carbonate ; but, before 

 attaining to this state, it may, unquestionably, react upon the organic 

 substances it encounters, disorganize them, favor their decomposi- 

 tion, in a word, behave as it does when used in composts. On the 

 other hand, in causing the destruction of organic particles already 

 in a state of decomposition, it must produce an unfavorable influ- 

 ence. 



Lime, previously quenched and cold, is generally spread by being 

 raked out from the cart upon the field, in little heaps, from five to six 

 or seven yards apart, each containing from half to two-thirds of a 

 bushel. It is or ought then to be spread immediately as evenly as 

 possible over the surface. There is only the disadvantage attending 

 this mode of proceeding, that slaked lime is twice the bulk of lime 

 in the shell or lump, and that, by slaking, it takes up at least one- 

 fifth of its original weight of water. There is saving of labor, 

 therefore, in distributing the lime unslaked, in heaps, and waiting the 

 slow process of extinction and pulverization by the moisture of the 

 atmosphere. The lime is often laid in a corner of the field, and 

 covered lightly over with vegetable earth to undergo pulverization, 

 and this plan answers very well. Sometimes the lime, before being 

 laid on, is worked up into a kind of compost with vegetable mould 

 and other matters ; this is all matter of calculation as to cost. If 

 our object be to supply the soil with the calcareous elements it wants, 

 the proper procedure is quite obvious. 



The mode of using lime with reference to other improvers of the 

 •oil vaiies in different places. In one place it is usual to lime and 



