Notes on the Geology of Swellenclam. 



109 



the author said, for his late friend, Mr James Brown, a young 

 chemist, who, by his labours and discoveries in the science to 

 which he had devoted himself, gave promise of an active and 

 useful life, which was, however, cut short by an attack of 

 cholera, that in a few hours proved fatal. His retiring manners 

 and devotion to his work made him unknown, save to a few 

 friends, who were thus unexpectedly called to mourn the loss of 

 one who seemed destined by his labours to command the respect 

 of the scientific world ; and the collection was some months 

 ago placed in the hands of the writer by his father. Ifc con- 

 sists of nearly 1000 different specimens, with accompanying 

 manuscripts, drawings, and sections, most elaborately exe- 

 cuted. Valuable memoirs had been published by Mr Bain on 

 the geology of South Africa ; but he did not seem to have 

 visited Du Toit, the locality where the fossils on the Society's 

 table had been gathered, as it was not mentioned by him. 

 Du Toit is about thirty-five miles north-west from Swellen- 

 dam. It is situated on the further side of the Lange Bergen 

 Mountains, on the oldest beds of what, from palseontographical 

 evidence, seems to be the Old Red Sandstone. The fossili- 

 ferous beds are composed of coarse sandstones and shales. 

 The fossils are chiefly brachiopod mollusca, and include 

 Spirifer antarcticus, and Orbignii, Terebratula Bainii, Orbi- 

 cula Bainii, &c, Solinella --antiqua, and other bivalves. 

 Besides these there were only some Encrinite stems, and the 

 cast of a Trilobite, neither of which could be more specifically 

 described, owing to their bad preservation. Mr Carruthers 

 noticed the remarkable condition in which the clay slates of 

 the metamorphic series exist in the vicinity of Swellenclam, 

 where they have little more consistency than dried alluvial 

 brick clays, so soft as to have permitted Mr Bain to drive a 

 tunnel of 400 feet through them by the aid of the pickaxe and 

 spade alone. The induration increases, however, until in 

 other localities the rocks become, as Mr Douglas says, " ex- 

 ceedingly hard, siliceous, and splintery, so as to cut the hand 

 when incautiously griped." 



