GIBRALTAR. 



crated to ihe lieight of 1439 feet ; the Rock-mortar, which 

 is the liigheft eminence to th» north, is 1350 feet ; and the 

 Signal-houfe, which is nearly the central point betwe^ii thcfc 

 two, is 1276 feet above the level of the fea. The weilern 

 fide of the mountain forms a fcries «f rugged flopes, inter- 

 fperfed with abrupt precipices. Its northern extremity is 

 perfectly perpendicular, except towai'ds the N. W., where 

 what are called the Lines intervene, and a narrow pafTao-e 

 of ground that leads to the iilhmus, and is entirely covered 

 with fortification. The callern iide of the mountain moftly 

 coniifts of a range of precipices ; but a bank of fand, rilinsv 

 from the Medirerranean in a rapid acclivity, covers a third 

 of its perpendicular height. Its foutl-.ern extremity falls in 

 a rapid (lope from the fummit of the Sugar-loaf into a rocky 

 flat of conhderable extent, called Windmill Hill. The 

 principal, mafs of the mountain rock confifts of a grey, 

 denfe marble ; the difl'erent beds of which prefent to Spain 

 i face of 1350 feet of perpendicular height, in a conical 

 form. Thele beds, or ftrata, are of various thicknefs, from 

 20 to upwards of 40 feet, dipping in a direftion from eafl 

 to weft, nearly at an angle of 35 degrees. In fome parts of 

 •the folid mais of this rock, we find teftaceous bodies 

 'entirely tranfmuted into the conftituent matter of the rock, 

 and their interior hollows filled up with calcareous fpar ; but 

 ■thefe do not occur often in its compofitien, and its beds are 

 not leparated by any intermediate itrata. This rock is 

 fuffering a flow, but conftant depofition ; and the uncovered 

 parts of it prefent holes of various fizes, hollowed out of the 

 folid rock, and apparently formed by tlie attrition of 

 gravel or pebble, fet in motion by the rapidity of rivers or 

 currents in the iea ; whence it is prefumed, that, however 

 high the furface of this rock may now be elevated above the 

 level of the fea, it has once been the bed of agitated waters. 

 On the well fide of the mountain, towards its bafe, ftrata 

 occur, which are of a different kind from the mountain 

 rock. (See Major Imrie's mineralogical Defcription of 

 Gibraltar in the Tranfaftions of the Royal Society of 

 Edinburgh, vol. iv. ) 



The firil, or higheft, forms the fegment of a circle, its 

 convex fide being towards the mountain, and its flope bi-ing 

 in that direclion. Tius llratum confifts of a number of thin 

 beds ; the outward one, which is the thinneft, is m a ftate 

 of decompofition, and is mouldering down into a blackilli- 

 brov.'n or ferruginous coloured earth. The beds below 

 this increafe progrcffively in breadth to 17 inches, where the 

 ilratification refts upon a rock of an argillaceous nature. 

 This latt bed, which is 17 inches thick, confifts of quartz of 

 a blackifti-blue colo\ir, in the fepta or cracks of which arc 

 found quartz cryftals, colourlefs and perfeftly tranfparent. 

 Thefe cryftals are compofed of 18 planes, difpofed in hex- 



' nngular columns, terminated at both extremities by hexan- 

 gular pyramids. The largeft feen by major Imrie, did not 

 exceed one-fourth of an inch in length ; they generally 

 adiiere to the rock by the fides of the column, but are 

 detached without difficulty. Their great degree of tranf- 

 parency has obtained for them the name of " Gibraltar 



' diamonds."' The rock is completely befet with batteries, 

 throv.Mi up at all points, where the afcent could not be ren- 

 dered completely inacceflible ; fo that from Europa Point, 

 which advances fartheft into tlie fea on the fouth fide, to 

 the higheil part of the rock, which is that of the north 

 (at about two miles diftance from the other), there is not a 

 fingle point, which is not ptit into a defenfible condition. 

 On the fide ncaroft Spain, the internal fortifications, made 

 fmce the time Gibraltar was befieged by the combined 

 ■armies of France and Spain, are aftoniftiing. Thefe im- 

 provements are principally owing to general O'Hara, the 



late governor ; a great ntimlcr of workmen having br 

 employed about it, for eight years, at an immcnfe cxpenc 

 In oroer to form fome idea of the labour expended on the 



•nee. 



r i- . -upended on thefe 



lortifications, it will be fufficient to obfcrvc, that the exca- 

 vations effeded by Uie force of gun-powder, in the centre 

 ot the mountain, and in the folid rock, form vaults of fuch 

 hciglil and extent, that during a fiege they are capable of 

 containing the whole garrifon. Thcfc caverns, of which 

 the moft confiderable is the hall of St. George, communi- 

 cate with the other batteries, cftabliftied aloi g the moun- 

 tains by a winding road, paffable on horfe-back. Oo 

 returning towards Europa Point, as you enter the town, 

 your attention is engaged by confiderable fortifications, 

 barracks, magazine.-,, and batteries, placed wherever the 

 nature of the ground would admit. On the higheft point 

 of land the tov.-er of St. George was built, under the direc- 

 tions of general O'Hara, wl:o intended to raife it to a 

 fufilcient height for commanding the whole of Cadiz, and 

 obfcrving all that palled in that port ; but tliC undertaking, 

 being difapprovcd by the Britifli government, was left in 

 an unfiniflied ftate. Along the mountain are fevcral grottos, 

 or natural excavations the moft famous of which is that of 

 St. Michael; the height of tlic entrance being 437^ (varas) 

 yards above the level of the fea. The cavern below is at 

 leaft 70 feet, and coiUains columns of cryftallizations and 

 ftalaftites, refcmbling all the orders of architecture. About 

 100 paces from its gate is another beautiful cavern, 65 \-ara« 

 fquare, and the vault 21 varas high. On the right is a 

 fecond excavation, adorned with caprices of nature fimilar 

 to thole of the former, but fo regularly difpofed, that it 

 has the appearance of a temple. Perhaps this was formerly 

 ufod for confulting fome oracle, probably that of Hercules, 

 who was the principal divinity of the place, as well as of 

 the cave in the promontory of Ampelufia, on the coall of 

 Africa. From tlie entry of this cavern you difcover the 

 whole of the bay of Gibraltar, two leagues' acrofs from eaft 

 to weft, and three from north to fouth. You alfo com- 

 mand a view of the country-houfes, the flower and kitchen 

 gardens, which the inhabitants have formed one above the 

 other, on the fide of the mountain, up to the royal road, 

 and the public walk, extending for about half a mile from 

 the town of Gibraltar to the new town on the foutli. The 

 Englidi have Ipared no pains in covering the rock with trees 

 and fiowers, in fupporting the earth with walls and props, in 

 cutting a number of roads through the folid rock, and in 

 making them paflaMe on horfe-back and in carriages up to 

 the very fummit. They have even fome artificial mea- 

 dows for their flocks. From the grotto of St. Michael, 

 fituated on the foutliem part of the mountain, at an almoft 

 equal diftance, the Signal tower and the Sugar loaf, the 

 entrance of which is 5000 fcct above the level ot the fea, you 

 difcover the magazines, the batteries, the new town ; on 

 the fouth, the marine hofpital, which is a handfome and 

 convenient building. The view extends over a number of 

 country-houfes, to fome of which beautiful <iMrdcns are 

 attached ; in time thefe new buildings will f«rm a town ai 

 confiderable as that of Gibraltar. Near thefe are eight 

 magi:ii"icent cifterns, large enough to contain 4O,cx>0 tons of 

 water, and bomb-proof; they receive all tlie water which 

 flows down the fide of the mountain, previoufly purified ia 

 coppers credled for the purpofe. On the foutli fide yo« 

 perceive a number of mountains, called Tarfes ; and liear 

 them formerly ftood a very ancient tower, with a ciilern and 

 well. In a cave not fai- diftant feveral ftones have been 

 found with human bones above the common fize, fo ftroncjlr 

 incrufted in them as to form one folid mais. (See F^^/e 

 JjO.vju.) FrQin Europa Point to the gate on the land-tide 

 H li 2 »rt 



