22,6 ■. Vefcription of the Table and the Paarlherg Mountains* 



coaft. In the heat of the fummer feafon, when the fouth- 

 eaifc monfoon blows ftrong at fea, the water taken up by eva- 

 poration is borne in the air to the continental mountains, 

 where, being condenfed, it refts on their fummits in the form 

 of a thick cloud. This cloud, and a low denfc bank of fog 

 on the fea, are the precursors of a fimilar but lighter fleece 

 on the Table Mountain, and of a ftrong gale of wind in 

 Cape Town from the fouth-eaft. Thefe effects may be thus 

 accounted for : — The condenfed air on the fummit of the 

 mountains of the continent, rufhes, by its fuperior gravity, 

 towards the more rarefied atmofphere over the ifthmus, and 

 the vapour it contains is there taken up and held invifible, or 

 in tranfparent folution. From hence it is carried by the 

 fouth-eaft wind towards the Table and its neighbouring 

 mountains, where, by condenfation from decreafed tem- 

 perature and concuffion, the air is no longer capable of 

 holding the vapour with which it was loaded, but is obliged 

 to let it go. The atmofphere on the fummit of the moun- 

 tain becomes turbid, the cloud is fhortly formed, and, hur- 

 ried by the wind over the verge of the precipice in large fleecy 

 volumes, rolls down the fteep fides towards the plain, threat- 

 ening momentarily to deluge the town. No fooner, how- 

 ever, does it arrive, in its defcent, at the point of tempera- 

 ture equal to that of the atmofphere in which it has floated 

 over the ifthmus, than it is once more taken up, and M va- 

 nifhes into air — to thin air." Every other part of the hemi- 

 fphere (hows a clear blue flcy, undifturbed by a Angle vapour. 

 The Paarlberg, on the left of the pafs into the valley, is a 

 hill of moderate height, and has taken its name from a chain 

 of large round ftones that pafs over the fummit like the pearls 

 of a necklace. Of thefe, the two that are placed near the 

 central and higheft point of the range are called, far excel- 

 lence, the Pearl and the Diamond • and a particular defcrip- 

 tion of them has been thought worthy of a place in the Phi- 

 lofophical Tranfaclions. From that paper, and Mr. Maflbn's 

 defcription, it would appear that thefe two mafles of ftone 

 refted upon their own bales, and were detached from the 

 mountain ; whereas they grow out, and form a part of it. It 

 has alfo been faid that their compofition was totally different 

 from the rocks that are found in the neighbouring mountain, 

 which led a naturalift in Europe to obferve, that thefe im- 

 menfe blocks of granite had probably been thrown up by 

 volcanic explofions, or by fome caufe of a fimilar nature. It 

 has been obferved in the preceding pages, that the fand- 

 ftone ftrata of the Table Mountain refted upon a bed of pri- 

 maeval granite, and that an infinite number of large ftones 



were 



