Journal of the Royal Agricultural Society/. 83 



nourishment in its mother's milk, or, by the admirable contrivance of nature, 

 in some similar substances. The body of a young chicken is formed from the 

 white of the egg in which it was enclosed; and the yolk is a provision for the 

 period which intervenes between its being hatched and the time when its little 

 bill is so hardened as to enable it to peck, and take up insects or small seeds. 

 The seed committed to the ground may be compared to an egg : the first 

 expansion of the embryo is entirely from the substance of the seed ; and, until 

 the seed-leaves are fully formed, it takes little or nothing from the soil, except 

 pure water. But after the real leaves expand, it requires more nourishment, 

 and if this is not found in the pores of the soil, or if the roots cannot penetrate 

 to it, the plant languishes and dies. It is of no use that plenty of rich manure 

 is somewhere in the soil, if it be not accessible, or if it be not in a proper statff 

 to be absorbed by the tender fibres of the roots. The plant will die, as an 

 animal would by the side of a chest full of provisions, which are locked up, or 

 unfit for his organs of digestion. These principles lead naturally to the best 

 practice in improving or cultivating the soil ; and we shall find that the mode 

 pursued by the Flemings admirably accords with the theory. 



" The trenching and mixing prepare the soil for receiving the additions of 

 organic matter. The roots are fed with a liquid manure readily, taken up, 

 and greatly invigorating, until a sufficient portion of humus is formed, which 

 gives the most gradual and regular supply of nourishment. At the same time 

 solid particles are deposited, which fill some of the pores, and begin that 

 accumulation of humus which in time will convert the whole into a rich and 

 fertile soil. 



" It must be observed, that the smaller the particles of sand the better the 

 soil will be after being improved. Coarse sand, each particle of which is a 

 visible crystal, allows the humus to be readily washed out. It must be mixed 

 with clay or marl to fill up some of its pores ; and if this is not already done 

 by nature it must be done by art, or all the labour bestowed on the cultivation, 

 and all the manure expended, will never be repaid by the produce. It is, 

 therefore, of the greatest consequence to all improvers of barren lands, to 

 know, not only what proportion of siliceous and argillaceous earths there is in 

 the soil, but also what is the actual size of the particles. This is very easily 

 ascertained by means of the simple instrument, consisting of metallic sieves, 

 which is described in the essay on the Analysis of Soils [Journ. JEng. Agr. 

 Soc, vol. i. p. 4)6.]. When a considerable proportion of the dry pulverised 

 earth passes through the finest sieve, it is a sure sign that the soil, if not 

 already fertile, can be easily made so. That which is most readily improved 

 consists of a small portion of coarse sand, mixed with a larger portion of finer, 

 and with a considerable portion of impalpable earth, partly siliceous and 

 partly argillaceous and calcareous, so that when it is moistened it does not 

 form a tough paste, but dries into clods easily pulverised between the fingers. 

 The degree of fertility will depend altogether on the quantity of humus which 

 is incorporated with this loam, and which the specific gravity readily dis- 

 covers, the richer soils being the lightest, for humus is much lighter than 

 any of the simple earths. 



" Keeping this in view, it is easy to show the advantage or disadvantage of 

 different modes of proceeding, which should vary with the nature of the 

 original soil. In the natural earth which has never been cultivated, or which 

 is dug up from a considerable depth below the surface, portions of different 

 kinds of earth are found in thin layers, or in separate pieces, which, being pul- 

 verised and mixed together, want nothing but the addition of humus to make 

 them a fertile soil. Here the use of the trenching-spade is evident. No other 

 instrument could so well divide the earths and mix them in due proportions. 

 The more the ground is stirred the better it becomes ; and, by a course of 

 cultivation which, instead of exhausting the humus, gradually increases its 

 quantity, it becomes at last a rich mould, like that of a garden in which all 

 plants suited to the climate thrive luxuriantly. In the progress to this state 

 of fertility the soil must have passed through every intermediate state; and the 



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