Stirring the Soil. 161 



what appears to be so advantageous a position ; and that soil 

 previously exhausted should be so renovated by mere change of 

 position is not the least inexplicable part of the business. That 

 all the improvement, however (unless manure has been at the 

 same time applied), which takes place proceeds from such a 

 cause, will readily be admitted by those who are aware of the utter 

 worthlessness of most subsoils, and who have remarked their 

 inveterate sterility after the surface has been removed, instances 

 of which, upon a large scale, must be familiar to many interested 

 in the subject; and those who have not such examples may 

 readily satisfy themselves by forming alternate beds of this and 

 top soil, in all other respects equal, when the worthlessness of 

 their favourite will become apparent, often characterised by 

 sterility so stubborn, that an immense expenditure in labour, and 

 in enriching and opening materials, is necessary to render it fit 

 for the purposes of the cultivator. Fertility conferred by trench- 

 ing is not of long duration, and the necessity for repeating the 

 operation becomes apparent : this would, no doubt, sooner be 

 the case, but for the entire change that has in the mean time 

 been effected in the originally worthless matter brought to the 

 surface, where continued cultivation, the action of the elements, 

 and the introduction of organic substances in the form of manures, 

 have turned it into matter capable of supporting vegetable life. 



Perfect pulverisation of the soil is admitted to be essential to 

 good culture ; yet, in the face of what passes as undisputed fact, 

 we see vast benefit conferred by placing upon the surface mat- 

 ter that for a time defies all attempts at this ; hence, in a great 

 measure, its undeniable barrenness, its unfitness to support vege- 

 tation, and possibly the cause^ in the first instance, of the benefit 

 conferred by placing it upon well pulverised soil, from its retain- 

 ing, by its comparatively impervious nature, a greater uniformity, 

 both as regards temperature and moisture, in the strata in which 

 we have seen that the roots delight to luxuriate. Although too 

 compact to be congenial to the tender rootlets, or too destitute 

 of available matter to afford them a supply of food, it never- 

 theless contributes something to their support, by affording them 

 a secure hold of the ground ; a matter of the utmost import, too 

 often neglected, and which the advocates of extreme porosity 

 seem to have entirely overlooked. That pulverisation might 

 often be advantageously carried much farther, I admit ; but the 

 extreme ought to be guarded against as decidedly injurious to 

 many crops, as the advantage derived from treading, rolling, or 

 any thing that tends to consolidate the soil, demonstrates. The 

 impolicy of such a practice is also strikingly manifested upon a 

 small scale, when sifted materials are used in the culture of plants 

 in pots, where it becomes so palpably injurious, that it is dis- 



3d Ser. — 1842. III. m 



