514 



THE SOUTHERN PLANTER. 



[September 



becomes fertile. Lime added to a clay soil 

 destroys that sticky, waxen consistence that 

 makes it so difficult to work, and prevents 

 the baking and hardening so fatal to vege- 

 table life. The addition of lime is not so 

 beneficial from its mere presence in a soil, 

 for generally there is enough for plant food; 

 but its good effect is chiefly owing to the 

 chemical changes it causes among the sub- 

 stances forming and existing in the soil. 



It has been long known that a mixture of 

 lime, earth, and rich organic matter, such 

 as manure and decomposing vegetable sub- 

 stances, causes the production of nitric acid. 

 Such a mixture is used in many parts of 

 the world to produce saltpeter, which is a 

 nitrate of potash. It is collected from the 

 earthy mixture by dissolving it in water, 

 which is evaporated, leaving the salt in 

 crystals. The same thing takes place in 

 the earth ; when lime is added to it, nitric 

 acid is formed, which combines with the 

 alkalies and earths in the soil, forming ni- 

 trates. These are all excellent fertilizers. 



The exact manner in which lime acts 

 upon the soil is not entirely understood, but 

 that it does produce a wonderful effect, 

 and a very beneficial one, is well known. 

 The limestone formations in the United 

 States are of very great extent. Our best 

 wheat soils overlie them. By analysis, we 

 find no carbonate of lime in these limestone 

 clays; yet it does not follow that lime is 

 not there in some shape. Accordingly we 

 discover it in the state of phosphate and 

 silicate. Upon these limestone soils lime 

 has been largely applied, and the result has 

 been excellent. We owe much to Mr. Ed- 

 mund Ruffin, of Virginia, for his practical 

 application of lime, and for his publications 

 in regard to it. By his efforts in this 

 respect a revolution has been created in 

 agriculture throughout the tide-water re- 

 gions of Viriginia. 



Some of the soils in the United States, 

 overlying limestone rocks, contain carbonate 

 of lime, while others are formed of a de- 

 composing limestone, or, as it is called in 

 Alabama, "rotten limestone." Here, of 

 course, we have lime largely in the soil. 

 This is not the case with soils overlying the 

 blue limestone of New York, Pennsylvania, 

 Maryland, and Virginia. The composition 

 of these soils shows a different origin. The 

 numerous and large springs throughout this 

 region form a great source to the soil of 

 carbonate of lime. This is insoluble; but 



the bi-carbonate, in which the lime has a 

 double quantity of carbonic acid, is soluble 

 and easily gives off a part of its carbonic 

 acid, returning to a carbona*e,arid to an 

 insoluble state. The springs bring up the 

 lime in solution, in a state of bi-carbonate, 

 which, upon exposure to the atmosphere, loses 

 a portion of its carbonic acid, and is deposi- 

 ted in the earth in the shape of limestone. 

 The most familiar example of this occurs 

 in a tea-kettle, which soon becomes incrust- 

 ,ed with limestone, if limestone water be 

 I used in it, from the cause we have men- 

 tioned above.- 



By far the largest portion of the soils 

 east of the Alleghany and Blue Ridge are 

 formed from the older and crystaline rocks, 

 and consequently contain less lime than 

 soils of a different origin, there being 

 neither limestone nor springs from lime- 

 stone rocks to impart it to them. All these 

 soils, without exception, would be benefited 

 by the application of lime. When using 

 the word lime, we would not wish to be 

 understood as meaning the result of burnt 

 limestone or shells only, but in whatever 

 shape it may be found, as marls, &c. 

 Lime, added in small quantities annually, 

 would seem, from experience, to have 

 a better effect than when put on the land 

 heavily at once. It is stated, on reliable 

 authority, that so small an amount as a 

 bushel to the acre has produced good effect. 

 In some parts of the country it is customary 

 to add burnt lime in great quantities, as 

 high as two hundred and more bushels per 

 acre. Utter sterility for sometime has been 

 the result of such profusion. Prudence 

 and economy would suggest smaller supplies. 

 Some care should be used in selecting the 

 limestone from which to make lime, as it is 

 seldom pure, often containing large portions 

 of magnesia and sand, and always more or 

 less phosphate of lime. The magnesia, if 

 not in too large quantities, can hardly be 

 objectionable. The phosphate of lime is 

 very desirable, and too much of it can 

 scarcely be applied. The sand in limestone 

 might be objectionable on the score of 

 economy, otherwise its use on a stiff clay 

 would be beneficial. Oyster shells might 

 naturally be expected to contain phosphate 

 of lime in considerable quantity, and these 

 are, perhaps, the best materials from which 

 to make lime for the farm. 



It must be borne in mind that lime of 

 itself will not give fertility to soil. The ma- 



