192 MINERALOGICAL DESCRIPTION 



fide of the mountain is a feries of rugged flopes, interfperfed 

 with abrupt precipices. Its northern extremity is perfectly 

 perpendicular, except towards the north-weft, where what are 

 called the Lines intervene, and a narrow pafTage of flat ground 

 that leads to the ifthmus, and is entirely covered with fortifi- 

 cation. The eaftern fide of the mountain moftly confifts of a 

 range of precipices ; but a bank of fand, rifing from the Medi- 

 terranean in a rapid acclivity, covers a third of its perpendicu- 

 lar height. Its fouthern extremity falls, in a rapid flope, from, 

 the fummit of the Sugar Loaf, into a rocky flat, of confiderable 

 extent, called Windmill Hill. This flat forms half an oval, and 

 is bounded by a range of precipices, at the fouthern bafe of 

 which a fecond rocky flat takes place, -fimilar in form and ex 

 tent to Windmill Hill ; and alfo, like it, furrounded by a pre- 

 cipice, the fouthern extremity of which is wafhed by the fea, 

 and forms Europa Point. Upon the weftern fide, this penin- 

 fular mountain is bounded by the bay of Gibraltar, which is 

 in length nearly eight miles and a half, and in breadth upwards 

 of five miles. In this bay the tide frequently rifes four feet. 

 Upon the north the mountain is attached to Spain by a low 

 fandy ifthmus, the greateft elevation of which, above the level 

 of the fea, does not exceed lo feet, and its breadth, at the bafe 

 of the rock, is not more than three quarters of a mile. This 

 ifthmus feparates the Mediterranean, on the eaft, from the bay 

 of Gibraltar on the weft. 



This mountain is much more curious in its botanical, than 

 in its mineralogical produdtions. In refpecft to the firft, it con- 

 nedls, in fome degree, the Flora of Africa with that of Europe. 

 In refpedt to the latter, it produces little variety ; perhaps a few 

 fubftances and phaenomena that are rare, but none that are pecu- 

 liar. 



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

 denfe (what is generally called primary) marble ; the different 



beds 



