148 A PRACTICAL TREATISE 



ried to 12 yards in diameter, and in that case generally con- 

 tain about 100 loads of ashes, at 3G bushels to tiie load. 



A nearly similar method is also much practised in Suffolk, 

 where the earth is burned in mounds, and it is called clod- 

 fmrning. The clods are raked together in small heaps of 

 from lour to eight bushels, at a rod distance, and burnt by 

 placing tliem ujxm a small quantity of haulm, or straw; but 

 this should be done very expeditiously, on the fire being pro- 

 perly kindled, as otherwise it would be exhausted before a 

 sufficient quantity was heated ; for which reason it is proper to 

 light them early in the day, that they may be well covered 

 before sunset. This, however, differs from paring and burn- 

 ing, as it is not requisite that any weeds, or roots of weeds, 

 should exist in the soil, for the real earth alone burns or chars 

 sufficiently; and as the smaller the heap, the less is the earth 

 calcined, it is thought by some that the better is the manure. 

 The idea is, however, probably erroneous; for these small 

 heaps are so quickly burned, that what is on fire at noon, may 

 be completed before night : if despatch be an object, that may 

 be attained by employing a greater number of hands, whereas 

 large piles cannot be effectually prepared without more con- 

 stant attention and delay ; but, like the process of kiln-burning, 

 this operation also requires some experience to carry on the 

 work expeditiously, and to burn close. 



Although the method of burning in heaps has the merit of 

 simplicity, yet the plan is objectionable, because this method 

 of managing the fire subjects it in many instances, to be either 

 extinguished, or to burn with such increased force as to con- 

 vert any portion of the earth which consists of clay, into mere 

 brick; besides occupying increased time and labour, and occa- 

 sioning an additional charge for cartage. It does not produce 

 guch good ashes as when the earth is calcined in a close kiln: 

 neither has the same quantity of fuel equal power; for, by the 

 erection of walls, the heat is effectually retained, and w-ill 

 continue for a long period after the fire has been extinguished; 

 whereas, in these round heaps, the air having full power over 

 every part of the surface, the internal heat is sooner checked, 

 and the smothering process — which is considered essential to 

 the value of the manure — cannot be so perfectly accom- 

 plished. Besides, as the walls are ultimately converted into 

 ashes, their cost only amounts to the trifling additional charge 

 of the labour of their erection. 



Burning with lime, is also a plan w hich has been adopted 



