362 Dr Davy's Agricultural Discourse. 



depths of the sea, because there is no higher ground near from 

 which it could have been conveyed by the action of water. A strik- 

 ing example of this is to be seen at the top of Horse Hill, imme- 

 diately above the road leading down to St Joseph's Church. Of 

 the kind of soil under consideration, excellent examples offer on the 

 estates of Bloomsbury, Welchman's Hall, and Blackman's. These 

 I particularise, because I have examined specimens of them, for 

 which I am indebted to their proprietors. 



Another quality of soils is that which prevails between the terrace 

 elevations, well marked in the valley of the Sweet Bottom, and per- 

 haps less distinctly in the more expanded and extensive valley of St 

 George. It contains more clay than the first mentioned, a large 

 portion of silica, and but a very small proportion of lime and mag- 

 nesia. Its colour is variable ; red and brown are its predominant 

 higher grounds. 



A third variety of soil, is that which differs but little from cal- 

 careous marl ; it is incumbent on a substratum of marl, consists chiefly 

 of carbonate of lime, contains fragments of sea shells, — contains but 

 a small proportion of clay and silica, and less of magnesia. It is gene- 

 rally of a light colour. It occurs in some parts of St Philip, espe- 

 cially its north-eastern part, in parts of St Michael's, and also of St 

 Lucy's, and probably elsewhere in many places. 



A fourth variety is a dark soil, in some situations almost black, a 

 colour which it owes to vegetable matter in a peculiar state of de- 

 composition, approaching, I believe, the state of peat. This soil 

 commonly contains a good deal of clay, with a sufficiency of cal- 

 careous matter, and of silica and magnesia. It occurs most com- 

 monly in low situations towards the sea coast, where there is little 

 declivity, where the drainage in consequence is imperfect, and there 

 is a tendency, when there is excess of rain, to stagnation. 



I shall mention only one other variety of soil, a calcareous argil- 

 laceous marl of a grey colour, consisting of alumine, carbonate of 

 lime, and of silica, in well adjusted proportions, with some carbonate 

 of magnesia. The most remarkable example of it that I am ac- 

 quainted with is on the Codrington College estate, below the cliff, 

 where, thrown up into steep hills and ridges, and depressed into 

 narrow valleys and ravines, it forms a little district apart, equally 

 remarkable for the barrenness of its aspect, its real fertility, its 

 abundance of water ; all I believe depending on the same cause, the 

 nature of the soil and subsoil. 



Other varieties of soil might be pointed out, but, in a discourse 

 such as this, with little advantage. They occur intermixed in one 

 or other of the principal varieties I have enumerated, for none even 

 of these, the principal varieties, are free from admixture to any 

 extent. How few estates, for instance, whether situated high or 

 low, are without marl : how few are without deposits or beds of stiff 

 clay. I am acquainted with one estate in St Lucy's, in which there 



