138 A PRACTICAL TREATISE 



arising- from the straw of the corn crops, should be invariably 

 applied to the land. 



Apjdicatioii. — It is obvious that in all cases the operation 

 of paring" and burning" must destroy a certain portion of vegeta- 

 ble substance, and it therefore can only be really useful where 

 an excess of this matter exists in the soil in a dormant state ; 

 for the accumulation of rank herbage and woody fibre, with 

 which some land is overrun, can only be slowly reduced to a 

 state of mould when left to the process of natural decomposi- 

 tion ; nor is it easily brought into a fit state for the immediate 

 purposes of cultivation, even by the application of lime. 

 Burning- has also the eflect of rendering clayey land more 

 friable in its texture, and consequently not alone better for 

 tillage, but also less retentive of water; for it has been ascer- 

 tained, that when clay has been burnt, its tendency to absorb 

 moisture from the atmosphere has been reduced in the propor- 

 tion of 7 to 2*. Thus the process, if judiciously conducted, 

 may change a soil which was tenacious, wet, and cold, into 

 one partaking of the opposite qualities, and therefore better 

 adapted to vegetation. The soils to which it is prejudicial are 

 tliose consisting principally of sand and flint, consequently, 

 containing little vegetable matter; for it destroys that which 

 is already in too small a proportion to secure the productive- 

 ness of the land. But pafing alone, without burning, may be 

 safely practised on such soils, when they contain root weeds, 

 and coarse herbage of difficult decomposition ; provided the 

 surface be then harrowed, so as to separate it from the earth, 

 and mixed with quick-hme, together with the scourings of the 

 neighbouring ponds and ditches, or clay, if it can be conveni- 

 ently procured, to form a compost. 



The following may be assumed as a summary of the best 

 practice: — Istly. To drain the land perfectly, and to lay it 

 dry, before commencing the operation. 2dly. To regulate the 

 depth of the paring by the nature of the turf, and the thick- 

 ness of the mat of coarse sward. 3dly. To burn the turf 

 slowly, but completely, so as to reduce the whole to ashes ; 

 yet carefully to guard against allowing the fire to take such 

 hold of the ground under the heaps, as to harden it into pits. 

 4thly. To spread the ashes upon a shallow ploughing, and as 

 fresh as possible — even hot ; as they operate more powerfully 

 in a caustic state than afterwards. 5thly. To mix lime in a 



♦Sir H. Davy, Elem. of Agric. Chem., 4to. p. 21. 



