156 OBSERVATIONS ON THE NATURE OF SOILS. 



changing their position in respect to atmospherical influence, and by a change in the 

 kinds of plants cultivated. All these improvements are independent of the appli- 

 cation of manure.'" For the most approved methods of performing these various 

 operations, and for many excellent remarks on the advantages to be derived from 

 them, I would beg leave to refer the reader to the admirable work above named, 

 as containing more ample and more valuable information on the subject than any 

 single work that has hitherto come under my notice. With these preliminary 

 observations on the general improvement of soils, I shall proceed at once to the 

 more particular object of this paper, which is to offer some practical hints on the 

 different soils used by gardeners for potting plants. Here the skill of the gardener 

 is frequently put to the test in the preparation of compost as substitutes for such 

 native soils as are not readily to be obtained. 



The different soils generally used for potting plants are, — 



Loam. — This is generally procured of the best quality from commons or old 

 pastures, taking only the top spit with the turf; that got from Sydenham 

 Common is reckoned the best in the neighbourhood of London. To be good, it 

 ought not naturally to crumble clown too fine, but should bear to be chopped up 

 rough with the spade. 



Peat. — This is of two kinds : 1st. That which is obtained from dry elevated 

 moors, containing a large portion of sand, and is seldom more than a few inches 

 deep : this is termed heath-mould, and is similar to that on Bagshot Heath. 

 2nd. That which is termed peat or bog-earth ; it differs materially from the first, 

 and is to be found in low swamps, where it is formed of decayed sphagnum and 

 other vegetable matter. This, as dug out, is worthless ; but after being frequently 

 turned and sweetened by exposure to the influence of the weather, is equally as 

 good as the heath-mould for potting, and is far superior for mixing with common 

 garden-soil in the borders out of doors, being even better than manure for im- 

 proving some sorts of stiff soils. 



Leaf-mould. — This is obtained by collecting leaves of any sorts of trees 

 (except the resinous kinds) in autumn, and laying them together to ferment and 

 decay. They ought to be turned and well mixed several times during the 

 summer ; and will require three or four years to get thoroughly rotted so as to 

 be fit for use. Of all trees the leaves of the common sycamore are perhaps the 

 best for leaf-mould, being somewhat succulent, and consequently sooner disposed 

 to decay. Oak-leaves are reckoned best to put into pits for giving a regular 

 bottom heat, but certainly not for leaf-mould, as they are completely dried up 

 before they fall. 



Rotted manure. — This is obtained by laying together a quantity of cow-dung, 

 and turning it over occasionally until it be so completely rotted as to appear 

 similar to black, rich mould. 



Sand. — This may be either dug from a pit or obtained from the banks of a 

 river ; if intended for mixing with soils, it should be a coarse grit ; but if wanted 



