192 THE COMPLETE FARMER 



proved in the same farm ; for the richer parts that were left 

 unlimed were uniformly inferior in produce to the poorer 

 that had been limed, during a period of not less than twenty- 

 one years, under the same course of management. 



Z. The principles on which lime operates as a manure. 

 Quicklime ir. powder, or dissolved in water, is injurious to 

 plants ; hence grass watered with lime-water is destroyed. 

 But lime freshly burnt, or slacked, forms a compost with 

 vegetable matter, w^iich is soluble in water, and nutritive to 

 plants. Mild lime (as chalk, or quicklime again impr.^gnat- 

 ed with carbonic ac'd) chiefly operates by improving the 

 texture of the soil and its relation to absorption. 



3. The various sorts of Limestone. Sometimes limestone 

 is almost perfectly pure, as is the case with marble, which 

 frequently contains scarcely any other substance but calcare- 

 ous matter. Several sorts of limestone, however, have mix- 

 tures of clay and sand, in various proportions, by w^hich the 

 efficacy of the manure, in proportion to the quantity of these 

 substances, is considerably diminished. It is necessary, 

 therefore, to analyze limestone, to ascertain the proportion 

 of pure lime, before it is advisable to use so expensive an ar- 

 ticle in great quantities, more especially if it must be con- 

 veyed from a distance. Bituminous limestone makes good 

 manure. But the magnesian is the species which requires 

 the greatest attention. Limestone sometimes contains from 

 20.3 to 23.0 of magnesia, in which case it would be injurious 

 to weak soils to apply more than from twenty-five to thirty 

 bushels per statute acre, though in rich soils double that 

 quantity may be used, and still more with peat, on which 

 soil it would have a most powerful effect in producing fer- 

 tility. 



4. Mode of preparing it for use. Limestone is burnt in 

 kilns of various constructions. It is applied with advantage 

 to soils recently reclaimed in a caustic state; but is gene- 

 rally slaclied, by throwing water upon the lumps, until they 

 crack and swell, and fall down into a fine powder. This 

 operation, when it is to be done, should not be delayed ; for 

 if properly burnt, calcined lime is easily reduced into a fine 

 powder, which may not be the case if the slacking be post- 

 poned. If water cannot easily be obtained, the lumps may 

 either be divided into small heaps and covered with earth, 

 by the moisture of which they are soon pulverized, or made 

 into large heaps, the lumps and earth six inches thick, and 

 the whole covered with earth. Where it can easily be had, 



