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strewn over with black angular stones ; in some the discolora- 

 tion had not penetrated far beyond the surface, and these stones 

 could at once be identified, with either the crystalline limestone 

 or the travertine crust. The colour which is discharged on 

 submitting the stones to a red heat, is doubtlessly of a vegetable 

 source ; not due to the growth of algals, because too deep and 

 lasting, but to the imbition of vegetable infusions, and their 

 subsequent partial decomposition -or carbonization. 



The recent sand dunes on the Bight coast attain considerable 

 elevations where they rest upon the Pleistocene sands or upon 

 the older tertiary escarpment ; the colour of the sand is usually 

 dirty- white or grey, sometimes snow-white, but never of the 

 reddish hue of the older series, though like them they contain 

 a very high percentage of calcareous matter. The view pre- 

 sented by the Peelunibie sand dunes, at the Head of the Bight, 

 as seen on a bright sunny day, is one not likely to be effaced 

 from the memory. To all appearance we were looking towards 

 a high mountain range whose base was encumbered with dark- 

 coloured rocks, and whose crown was laden with snow. The 

 illusion was strangely perfect, for the so-called snow and the 

 rocks were as uniform and apparently consistent as though 

 they were the genuine components of an Alpine landscape. As 

 we approached, the wonderfully beautiful and refreshing 

 spectacle gradually lost its grandeur, through diminution of its 

 apparent height and massiveness ; and finally the black coloured 

 rocks were seen to be the dark green foliage of bushes, and the 

 snow to be the domed tops of white sand dunes whose bases 

 were clothed with shrubs. The whiteness of the sand is due to 

 the fragments of bleached shells of Donacilla elongata, which 

 constitute the whole or nearly the whole of the coarser part of 

 the sand ; whilst the finer part, which is less than a moiety, is 

 comminuted shelly matter, though of not so white a colour. 

 These sands have a maximum elevation of 180 feet, but this 

 height is only attained where they have surmounted the 

 escarpment of the older tertiaries. 



The only permanent water in the country around the Bight 

 is derived from the sand dunes and Pleistocene sands. Water 

 is, however, not always procurable in the sand dunes, the 

 supply being most abundant in those which are devoid of 

 vegetation. At Fowler's Bay water is thrown to the surface 

 by the pipe-clay of the Talata swamp ; but in most instances 

 the fresh water is simply buoyed up by the sea water. 



The Soil of the Bunda Plateal* is a reddish coloured loam 

 or loess, and near the coast has a thickness of as much as eight 

 to ten feet ; and in its upper two feet or so is crowded with the 

 shells of Helix and Bulimtis. Its thickness diminishes beyond 

 the northern boundary of the oasis, and in the more interior 



