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Note on certain detached Rocks in JBarbadoeSy and on the 

 Formation of Agaric Mineral By John Davy, M.D., 

 F.R.S., London and Edinburgh, Inspector-General of 

 Army Hospitals. Communicated by the Author. 



Amongst the more striking objects which attract the atten- 

 tion of the inquiring traveller in Barbadoes, may be men- 

 tioned the great masses of detached rock of coral and shell 

 limestone which occur dispersed here and there, chiefly in 

 its north-eastern part, — a part which, as regards its strata, 

 may be considered analogous either to the old red sandstone, 

 or, at latest, to the new red sandstone formation ; and which, 

 as I have already pointed out in a former communication, is 

 remarkably contrasted with the other and greater portion of 

 the island, and I may now add, with those masses of rock 

 that may be held to represent this portion. Between the two 

 parts there is a limitary line of inland cliff, similar in its 

 structure to the detached rocks. It is generally supposed 

 that these masses are derived from the cliff, broken off, and 

 somehow removed to the spots where they are now found. 

 That this is their history in many instances can hardly be 

 doubted ; as where they are met with under the cliff, or even 

 at the distance of two or three miles, where an inclined plane 

 intervenes. But there are other sites on which they are to 

 be seen, to which such an explanation is hardly applicable, 

 • — as on rising grounds and hills, with hollows and valleys 

 intervening, over which, by the mere force of gravity in fall- 

 ing, they never could have passed, — leading to one of two 

 conclusions, either that the valleys referred to have been 

 formed since the detached masses were separated, or that 

 other causes have been in action besides those presumed in 

 the foregoing supposition, but of what kind, whether glacier 

 or volcanic, it may be difficult to determine. 



These detached rocks are commonly covered with wild 

 plants, and, in consequence, with their steep sides and often 

 castellated forms, have a very picturesque appearance in the 

 landscape, especially contrasted, as is often the case, with 



