104 A PRACTICAL TREATISE 



quality as to occasion sterility, this mixture of fresh earth 

 along- with the surface-soil and lime will prove highly advan- 

 tageous. Virgin earth, indeed, if not in itself a manure, 

 readily unites with lime, and richer composts are thus made 

 tlian with earth taken from the surface : the expense, too, is 

 less, for a smaller quantity of lime can be made to answer the 

 purpose. The lime should then be laid on in the state of shells, 

 before it is slaked, and ploughed well in, to insure its complete 

 combination ; the loose earth which escapes from the side 

 furrows should then be shovelled up and thrown over the heap, 

 after which a fermentation takes place within a very short 

 time, if the weather be damp and warm, and the compost 

 should be immediately laid upon the land, in quantity accord- 

 ing to the quality of the soil to which it is to be applied. 

 From 40 to 50 double cart-loads have been found a full dose 

 to ordinary land, of which only one-seventii part of the com- 

 post was quicklime, which was considered equal in force to 

 one-third of that which had been slaked. Nothing, however, 

 can be more uncertain than the quantity of lime required, for 

 it depends both upon the quality of the lime and of the earth 

 with which it is to be mixed, as well as the state of the 

 weather; but, from trials which have been frequently made, 

 it would seem that two bushels of lime-shells will be sufficient 

 for a cubic yard of earth of average quality ; and 64 cubical 

 yards of the compost — when properly prepared and applied to 

 the soil — may be deemed a moderate dose for an acre of land; 

 indeed, 40 have been considered a good dressing for light 

 land, though more might unquestionably be, in most cases, 

 laid on with better effect.* A dressing of this kind has been 

 frequently found more effectual than one of farm-yard dung. 



We cannot close this chapter without also adverting to the 

 very just opinion generally entertained, that ^ soils ought to 

 be crossed ;' or, in other words, that composts, of which clay is 

 the basis, should be administered to light soils ; and the reverse. 

 The expense is, however, in most cases, so enormous, in con- 

 sequence of the vast quantity which must be laid on to produce 

 any sensible effect, as seldom to leave any profitable result. 



* 'If 80 cubic yards are considered to be a pood medium dressins; for a 

 Scotch, or 64 for an English acre, 160 bushels of lime-shells will be sufficient. 

 Now, the length of a head-ridpe opposite to four ridges of 18 feet is 72 feet, 

 and its breadth 18 feet. If this space be ploughed 10 inches deep, it will 

 produce 40 cubic j-ards of earth at each end of the ridges; while the whole 

 work may be executed by horse-labour.' 



