surface of the rock, and four feet above high-water mark; and although considerable pains were taken to discover its outlet, no communication of the kind was found.
Mr. Whitby mentions that caverns have been frequently discovered in this limestone, the walls of which have been encrusted with stalactitic concretions; but in the present case no such appearance was observed in any part of the cavity, a proof, says the author, that no opening in the rock from above had ever been closed up by the process of infiltration. In further confirmation of this circumstance, Mr. Whitby has stated that in the contract for quarrying there are two prices; one for rock, and another for clay, earth, and rubbish; and that two officers constantly attend, one for the Crown and the other on the part of the contractors, who measure the contents of all caverns containing clay or other soft materials; and that these officers distinctly state that the rock surrounding the cavern was equally hard with the other parts.
All the bones discovered in this place belong to the rhinoceros, and are evidently parts of the skeletons of three different animals. They are in a most perfect state of preservation, and every part of the surface entire, to a degree very seldom observed in fossil bones; and as the teeth of the rhinoceros differ both in form and structure from those of every other known animal, there was no kind of difficulty in recognising them. Every portion of the bones also possessed some characteristic feature proving it to have belonged to the same animal. The animals to which these bones belonged seem to have been nearly of the same size, and very large, for on comparing the fossil metacarpal bone, with that of the largest rhinoceros ever seen in this country, the skeleton of which is in Mr. Brookes's collection, that of the former was 818 inches long and 214 inches broad, while in the latter the length was only 718 inches and the breadth 218 inches. This skeleton stands 5 feet 8 inches high. It deserves remark that all the bones found in this cavern belong to the same species of animal; for although great pains were taken to ascertain whether there were any others than those sent to London, none were discovered.
Some comparative chemical analyses of different fossil bones are annexed to this paper, from which it appears that those above described are remarkably free from extraneous earthy substances, and consist almost entirely of phosphate and carbonate of lime, with only slight traces of animal matter: whereas most of the fossil bones discovered in the blue clay at Brentford, and in the argillaceous limestone at Lyme in Dorsetshire, yielded considerable portions of aluminous and siliceous earth.
