398 On Maiden, or Virgin, Soil. 



ground has to be minutely pulverised. In very deep soils re- 

 quired to be very long under cultivation, and where the expense 

 is not so much a matter of calculation, owing to the high rent 

 of the land, it might be beneficial to trench to the depth of 

 three spadings and shovelings, alternately with the two. Where 

 the subsoil is a red ferruginous clay, or a cold blue clay, the 

 work should be done more cautiously ; a little new soil only 

 should be brought up at. a time, and a plentiful sprinkling of 

 quicklime, especially to the first sort, bestowed. Even where 

 the subsoil is a red ferruginous gravel, it will be of benefit to 

 turn up a portion of the iron to the action of the air : the more 

 soluble protoxide of iron will be converted into peroxide, and 

 become less soluble and not so dangerous ; and if much sulphate 

 of iron exists, which is soluble, and very hurtful in excess, the 

 quicklime will be beneficial in decomposing it. Too little at- 

 tention has been paid in theory to the mechanical condition of 

 the soil. In the same field there are often very different qualities 

 of soil, which suit one condition of the weather better than 

 another ; and the reverse takes place in other seasons. Dif- 

 ferent kinds of manure and crops are also suitable to different 

 qualities of soil. One condition of the soil and weather may 

 require the surface to be left as open as possible, while rolling 

 and consolidation may be more suitable for another. Experi- 

 ments in measured quantities afford a powerful and apparently 

 accurate means of obtaining information; but, if the above state- 

 ments are not attended to, very wrong conclusions may be ar- 

 rived at. 



The theoretical cause of the good effects following a renewal 

 of the surface, by bringing up virgin soil, has been talked of as 

 involved in mystery, and some unknown property in maiden 

 soil has been sought for as the cause of its benefits ; but, if we 

 take into consideration the immense effect produced by a proper 

 mechanical state of the soil, the stomach of the plant, where un- 

 digested substances are fitted for absorption, we can have little 

 difficulty in assuming that as the principal cause. The reason 

 why maiden soil keeps more compact in the particles when di- 

 vided is, the tendency which rocks have to disintegrate, and, 

 when again submitted to superincumbent pressure, to begin again 

 to resume the state of stone. That the first cause is in action, 

 we may have every day experience, by seeing the effects of mois- 

 ture and heat long continued on rocks, aided by the action of 

 the carbonic acid, oxygen, &c, of the atmosphere. We may see 

 the solid rocks cut through to an immense depth by the action of 

 water ; and we may also see them crumbling to pieces, not less 

 effectually though more slowly, under the ordinary operation of 

 heat, air, and moisture. That this action continues after the 

 pieces of rock have been brought together in a mass, and mixed 





