4 VOELCKER on the Scouring Lands 



most scouring districts on the Polden Hills ; and on that occasion 

 I took on the spot samples of water from a stream of water from 

 the lias-cutting of the Bristol and Exeter Railway at Dunball, 

 and from a stream of water which breaks out at Ford Farm on 

 the south side of the hill between the parishes of Edington and 

 Stawell. Both these waters are known to possess scouring pro- 

 perties : I was therefore particularly anxious to examine them. 

 I further took samples of scouring land situated in the parish of 

 Cossington ; likewise hay from scouring land at Meare, and hay 

 from peaty land that does not scour. These different samples 

 and a soil from scouring land on the estate of Sir Alexander 

 Hood at Shepton Mallet, as well as a peat soil at Meare, kindly 

 sent to me by Mr. Poole, were carefully examined in my labora- 

 tory. The whole investigation into the causes of scouring so 

 prevalent on certain pastures in Central Somerset engaged my 

 liveliest attention. 



The analytical proofs, which require to be mentioned in support 

 of the views entertained by me at present on the subject of this 

 report, may be conveniently incorporated in the examination of 

 the leading theories to which allusion has been made. 



For the sake of brevity, the hypothesis which supposes some- 

 thing injurious to vegetation to predominate in lias-clays may be 

 termed the Geological Theory. This will claim our attention in 

 the first place. In the next place the Drainage Theory requires 

 examination ; and the rest may be considered together under the 

 general head of Herbage Theories. 



Examination of t/ie Geological Theory. 



The question whether or not there is anything injurious or 

 abnormal in lias-clay soils admits of a direct solution, which must 

 be sought in the analysis of soils pre-eminently distinguished by 

 scouring properties. Accordingly an analysis has been made of 

 such a soil from Mr. Rugg's farm, in the parish of Cossington. 

 The following results were obtained : 



Composition of Scouring Land from Mr. Rugg's Farm, Cossington. 

 August, 1861. 



Moisture 4'73 



Organic matter and water of combination .. 16'57 



Oxides of iron and alumina .. .. 14'26 



Carbonate oflimc 5-25 



Carbonate of magnesia .. 3*67 



Alkalies 1-Q4 



Insoluble siliceous matters 54'4S 



100-00 



