C isi 3 



on washing a sterile soil it is found to contain the salt?, 

 of iron, or any acid matter, it may be ameliorated by 

 the application of quick lime. A soil of good ap- 

 parent texture from Lincolnshire, was put into my 

 hands by Sir Joseph Banks as remarkable for steril- 

 ity : on examining it, I found that it contained sul- 

 phate of iron ; and I offered the obvious remedy of 

 top dressing with lime, which converts the sulphate 

 into a manure. If there be an excess of calcareous 

 matter in the soil, it may be improved by the applica- 

 tion of sand, or clay. Soils too abundant in sand are 

 benefited by the use of clay, or marie, or vegetable 

 matter. A field belonging to Sir Robert Vaughan at 

 Nannau, Merionethshire, the soil of which was a light 

 sand, was much burnt up in the summer of 1 805 ; I 

 recommended to that gentleman the application of peat 

 as a top dressing. The experiment was attended 

 with immediate good effects ; and Sir Robert last year 

 informed me, that the benefit was permanent. A de- 

 ficiency of vegetable or animal matter must be sup- 

 plied by manure. An excess of vegetable matter is 

 to be removed by burning, or to be remedied by the 

 application of earthy materials. The improvement of 

 peats, or bogs, or marsh lands, must be preceded by 

 draining ; stagnant water being injurious to all the 

 nutritive classes of plants. Soft black peats, when 

 drained, are often made productive by the mere appli- 

 cation of sand or clay as a top dressing. When peats 

 are acid, or contain ferruginous salts, calcareous mat- 

 ter is absolutely necessary in bringing them into culti- 

 vation, When they abound in the branches and roots 



