BEEAKING UP OF OLD GEASS LAND. 127 



char away to ashes. If the land is suitable, the ashes will be red 

 and powdery, mixed with a few black particles, and when put 

 into water will make it more or less muddy. In the proportion 

 that the water holds the ashes in suspension will the land be 

 benefited by burning. If the land is unsuitable, the ashes will 

 be sandy, and instead of making the water thick they will 

 be precipitated to the bottom, leaving the water almost clear. 

 Supposing this experiment to be in favour of the operation, even 

 then only a small area should be tried until there is conclusive 

 evidence that the proceeding would be advantageous. 



There is no necessity to pare the soil deeper than three or 

 four inches, and instead of the spade or turfing iron, a paring 

 plough made for the purpose is to be preferred, especially as it 

 leaves the shce of soil on its edge, so that a drying wind soon fits 

 it for being gathered into heaps. To economise labour, many 

 small fires scattered over the field have been advocated, and 

 undoubtedly they save much carrying of the turf and facihtate 

 the spreading of the ashes. But small heaps are very wasteful. 

 It is almost impossible to prevent them from flaring, and that is 

 ruinous. Large dense masses, however, can be burned slowly 

 and evenly, and at a comparatively low temperature. This point 

 is worth close attention, for it makes an enormous difference in 

 the fertihsing value of the ash. The inorganic constituents of the 

 soil are rendered soluble when burnt slowly, and become more 

 insoluble when overburnt. 



The effect of burning is to get rid of all the organic matter. 

 But the mineral constituents — with the exception of nitrogen, 

 which plant-life had abstracted from the soil— remain, and they 

 are so transformed by fire as to be easily assimilable by future 



crops. 



The consumption of all the organic matter by fire is of 

 course a destructive process, and in itself involves a consider- 

 able loss, but the effect of fire upon the inorganic substances 

 goes far to neutralise this loss. The soil is rendered capable 

 of assimilating ammonia, nitrogen, and other plant foods more 



