*2ii TrohnhhOrlglti of the FoJllBone: at Gibraltar. 



' ttiat thc'mriteriais had been carried in at various periods, and that' thofe periods baVebeen 

 'very remote from each other. 



• ArUofia Bay, upon the Wfeft fitJe of Gibraltar, this cbtierelion' is found in what has evi- 



• dently been a cavern, Originally formed by huge unfhapely maffes of rock, which have 



• tuiTibled in together. The filTure or cavern formed by the difniption arid fubfidence of thofe 

 mafles has been 'entirely filled tip wMth the toncretion, and is'nov/ expofed to full view by 

 the outward mafs having dropped-down in ccftifetjuence of the encroachments of the fea. It 



■ isto this fpotthat ftrangtrs are generally led to examine'the piienomenon; and the compo- 

 fition having here attained toils greateft degree of hardnefs and folidity, the hifty obfcrver, 



"feeing the" bones -entlofedln what has' fo little" the appearance of having been a vacuity, ex- 

 amines no farther, but immediately adopts tlic idea' of their being incafed in the folid rock. 

 'The con>munication from this- former chafm to the furfacc, from whicn it ha? received the 

 materiaJs-of the concretion, is {Vill to be traced in the face of the rock; but its opening is at 

 prefent covered by ihe''bafe of the Tine wali ttf the garrifon. Here bones are found that ate 

 apparently human; and thofe of them tliat appear to be of the legs, arms, and vertebras of the 

 back, are fcattercd among others of various kinds and fizes, even down to the fmalleft bones 

 of fmalT birds. IFound here the complete jaw-bone of a flieep ; it contained its full com- 

 plement of tee'tb, the enamel of which was perfect, and its whitenefs and luflrein ho de- 

 gree impaired. 'In 'the hollow parts of fome of the large bones was contained a minute 



• cryftallfzation of^pure and colourlefs calcareous fpar ; but in mofl; the interior part confifted 

 < of a Tparry cruft of a reddifh colour, fcarcely in any degree rranfparent. 



'At the northern extremity of the mountain the concretion is generally found in perpen- 

 dicular fiffures. The miners there employed upon the fortifications, in excavating one of 

 thofe fifllires, found, at a great depth from the furface,twoflculIs, which were fuppofed to be 

 human ; but to me one of them, if iTOt both, appeared to be too fmali for the human fpecies. 

 The bone of each was perfeflly firm and folid; from which it is to be prefumed that they 

 were in a ftate of maturity before they were encldfed in the concretion. Had they apper- 

 tained to very young children, perhaps the bone would have been more porous, and of a lefs 

 firm texture. The probability is, that they belonged to a fpecies of monkey which ftill con- 

 tinues to inhabit in confiderable numbers thofe parts of the rock which are to us in- 

 acceffible. 



This concretion varies in its compofition according to the fituation in which it is found. 

 At the extremity of the Prince's lines, high in the rock which looks towards Spain, it is found 

 to confift only of a reddifli calcareous earth, and the bones of fmall birds cemented thereby. 

 The rock around this fpot is inhabited by a number of hawks, that in the breeding fcafon 

 neftle here and rear their young: the bones in this concretion are probably the remains of 

 the food of thofe -birds. At the bafe of the rock below King's lines the concretion confifts 

 of pebbles of the prevailing calcareous rock. In this concretion, at a very confiderable 

 depth under the furface, was found the under part of a glafs bottle, uncommonly fliaped, and 

 •«f great thicknefs ; the colour of the glafs was of a dark green. 



In many parts of the rock I have found concretions in which there are no bones of any 

 kind ; and on the elevated parts of the mountain, where the flopes are rapid, I have found a 

 breccia (if I may fo call it) entirely confifting of fnail-fhells combined in a mafs of opaque 

 ftala<Sitical fpar of a yellowifli brown colour. The various progrellive augaientations of this 



matter 



