90 the farmers' handbook. 



In a note in the Agricultural Gazette oj New South Wales, vol. XX [V r 

 (1913), page 601, Mr. A. J. Wilson describes a method adopted in South 

 Australia, on the Murray, which is as follows : — 



"A 12 to 14 feet cube is excavated, with a trench 2 feet wide .slanting to 

 the bottom for lighting purposes: Pieces of thick wood are laid at intervals 

 of about 3 feet, and in between are put dry boughs. «fec, for lighting. The 

 fire can then spread all over almost immediately, and the lime will be evenly 

 burnt. The first layer of wood is put crosswise on the bottom pieces, and 

 then alternate layers of stone and wood not more than 18 inches thick, 

 finishing with a layer of wood. This ensures the top stone being burnt." 



In places where limestone occurs and wood or other fuel is abundant, one 

 or other of the above methods, or a similar method, will give satisfactory 

 results, while avoiding the expense of the construction of a kiln. 



Action of Lime on Different Soils. 



The action of lime in the first place is a mechanical one, in altering the 

 texture of the soil, and with it those properties which depend upon its 

 texture, such as its absorptive power for water, its amenability to tillage 

 operations, &c. The action of lime upon a clay soil may be illustrated by 

 the following experiment : — If a small quantity of a heavy clay be mixed 

 with water in any suitable vessel, it will form a muddy liquid. If a little 

 lime be added to this, and the mixture well shaken, it will be noticed that 

 the solid matters sink to the bottom in a loose powder, and in a short space 

 of time, if the water is poured off and the soil dried, it can be readily 

 broken up by the fingers. If no lime had been previously added, the clay, 

 on drying, would form a hard mass, difficult to break up. This action, which 

 is due to the power that the lime has of coagulating the fine particles of the 

 clay, is identical with what takes place on the larger scale when lime is added 

 to the field. 



The presence of lime also prevents the shrinkage which wet clay soils undergo 

 on drying, and which causes the cracks and fissures seen on the parched clay 

 soil. The admixture of lime to a clay, therefore, prevents the formation of 

 a sticky mass when wet, and a cracked, parched appearance when dry. 



Limed land is drier and warmer, more friable, and consequently more 

 readily cultivated than unlimed land. Land which has been limed is ready 

 for the plough sooner than unlimed land. 



On light, sandy soils, the action of lime is also strikingly benefieial in 

 binding the particles of sand together, and increasing the cohesive and 

 capillary power of the soil. Its action is, in fact, exactly that of lime on 

 sand in the mixing of mortars, only on a much modified scale, since for 

 making mortar the proportions are one part of lime to three or four parts of 

 sand, whereas the addition of a ton of lime per acre represents one part of 

 lime to nearly 20,000 parts of sand. The action of the lime is the same in 

 both cases — on drying it absorbs carbonic acid from the air, forming carbonate 

 of lime, which cements the particles of sand together ; forming, in the 

 proportions used in making mortar, a hard compact mass, and, in the case of 

 the soil, increasing its cohesiveness and its power of retaining water. 



Lime, therefore, lessens the cohesiveness of clay soils, and increases that of 

 sandy soils — two properties which are apparently opposed to one another — in 

 fact, there are few soils the mechanical texture of which is not improved by 

 liming. 



The action of slaked lime is exactly the same as that of stone or quicklime, 

 but not so pronounced, and it is generally preferable to use the lime powdered 

 and unslaked, or only slightly and freshly slaked. 



