468 



NATURE 



{March 20, 1879 



bour, and disappearing from view, only to be succeeded 

 'by higher and higher strata above them. No better 

 'example of this could well be found than the map of 

 Natal of Mr. Griesbach ; the rocks all run parallel to the 

 sea-coast, striking into the Zulu territory, and dipping 

 steadily the one after the other into high ground, form- 

 ing the watershed between the Indian and Atlantic 

 oceans. The eastern or seaward belt about fifty miles in 

 vridth, consists of ancient mica-schists, resting on granite 

 and gneiss seen at the bottom of the deeper valleys, the 

 whole surmounted by the "Table Mountain Sandstone," 

 of carboniferous age, forming extensive plateaux, lying 

 perfectly flat on a horizontal surface of clay-slate, and 

 broken by lines of fault, into a series of steps, plateaux 

 rising above plateaux, with precipitous sides to a height of 

 2,300 feet between the sea and Pietermaritzburg, where 

 the country again descends to 2,080. These table- 

 lands are covered with extremely poor soil, supporting a 

 dense grass vegetation, on which feed numerous herds of 

 cattle ; not a shrub occurs to enliven the endless uniformity 

 of the scene, broken only by the ravines formed by the 

 "tivers cutting down through the sandstones to the granite 

 and old rocks beneath, often forming precipitous cliffs 

 several thousand feet high, the vertical drop, from the 

 Krantzkop Mountain to the River Tugela being nearly 

 3,800 feet. The top of this mountain is composed of 

 melaphyre ; these melaphyre greenstones contain copper 

 ores and strike south-westwards to the Ihgeli range in 

 Kafifirland. 



At Pietermaritzburg, the next belt of country com- 

 mences, the town being built on the basement beds of the 

 Karoo formation, belonging to the Dicynodon beds of 

 'South Africa, of triassic age, the name being given from 

 the "karoos," or immense plains of the interior, forming 

 the largest part of South Africa, including the elevated 

 tract of " Kalahari, the Free States, and the Transvaal, 

 as well as the country to the north, as far as Limpopo." 

 They are present in the Zambezi, and rise to a height 

 of 12,000 feet in Mont-aux-Sources, in the Drakenberg 

 Mountains. The base of the Karoo series rests uncon- 

 formably on the carboniferous table mountain sandstone, 

 and consists of large angular blocks of transported granite, 

 greenstone, and gneiss, in a matrix of clay and grit. They 

 occupy a large area, and pass under plant -bearing shales. 

 These boulder beds have been ascribed a glacial origin 

 by Dr. Sutherland, Surveyor-general of Natal. Mr. 

 Griesbach points out the overlying plant-beds corre- 

 spond to the plant-beds of Southern India, associated 

 with Dicynodon remains, and also resting on a boulder 

 bed (Talchir group). 



The great Karoo plains, Dr. Grey is inclined to regard 

 as the bed of an inland sea ; salts of soda predominate 

 largely in the salines of the soil, and assist in forming the 

 *' background" of this region (sandy soil, with salt, car- 

 bonate of soda, and some salts of magnesia and alumina). 

 Its surface forms the sweet-grass country of the Dutch 

 *' Zout- Veldt," yielding the valuable Karoo plant (/4^,?«- 

 cho2ra parvlflord). In this tract the climate is most 

 salubrious, and the higher the country ascends the more 

 fruitful is the ground. The yellow wood flourishes, wheat 

 and European fruits flourish, and the cold of the winter, 

 though not so severe as that of northern Europe, braces 

 the European settler, and agrees with his constitution. 



Fringing the Natal shore, there is a narrow belt of the 

 Karoo formation, resting unconformably on the table moun- 

 tain sandstones and older rocks, so that the latter form an 

 exceedingly low and flat-topped anticlinal arch, throwing 

 ofl'the Karoo beds on either side. Landward these rise 

 to the Drakenberg, seaward they have for the most part 

 been denuded away, though their presence in Southern 

 India points to the former extension over what is now the 

 Indian Ocean of a series of lakes fringed by lands covered 

 -with plant growths, extending over Southern India, and 

 ■parts of South Africa. The investigations of Mr. Blan- 



ford in Southern India support the views of Prof. Huxley 

 and Mr. Sclater as to the existence of an extending sub- 

 merged mesozoic continent, "Lemuria," which, was 

 shadowed forth in Mr. Darwin's researches on coral reefs. 

 Mr. Blanford comments strongly on the great relation 

 between the plants of the Indian and Australian (New 

 South Wales) coalfields, many of the species being 

 identical, the two localities being no less than 5,550 miles 

 apart. In India these plant-beds rest on the supposed 

 glacial (Permian ?) beds of the Talchir group, the 

 included scratched blocks being often forty-two reet in 

 circumference. ,'\ ' 



The Karoo boulder bed is described by Dr. Sutherland 

 as containing well-scratched blocks, inclosed in a material 

 which has since been metamorphosed, and resting on 

 scratched old Silurian sandstones. The characters of 

 the various members of the Karoo series is well capitu- 

 lated by Prof. Rupert Jones in Mr. Ralph Tate's 'paper 

 on South African Jurassic marine mollusca, the sequence 

 being : Stormberg beds (Huxley) ; Beaufort Beds ; Koo- 

 nap beds, and Ecca beds. The Beaufort beds most 

 closely correspond to the Dicynodon beds of India, the 

 boulder beds in both countries, according to Mr. Blan- 

 ford, being pre-triassic, and he carries back his Indo- 

 oceanic continent to Permian times, and extending up to 

 a late Jurassic epoch — South Africa, India, and Australia 

 being connected at the early part of the period, Africa 

 and India, up to the end of the miocene. 



In 1824, some caves called Izinhluzabalungu \vih\iQ 

 men's houses) were discovered by Mr. Fynn to be fossili- 

 ferous ; the name, given by the natives, was due to ship- 

 wrecked sailors having taken up their abode in them. 

 In 1 85 1 Capt. Garden had his attention called to these 

 fossils, especially some gigantic Inocerami, two feet by 

 one foot, by his servant, named Thomas Souton, a Private 

 in the 45th Regiment, after whom one of the fossils 

 obtained was named by Mr. Baily, who examined them at 

 the request of the late Prof. Forbes. The deposit occupies 

 a small tract on the south end of the colony, and, as Mr. 

 Baily pointed out, may be correlated with the lower 

 cretaceous of Southern India, one species Peden quin- 

 quecostattis being common to the English greensand. 

 The investigations of Mr. Griesbach have largely added 

 to the number of the species, and supported Mr. Baily' s 

 conclusions, twenty-two of the species occurring in India, 

 thirteen being peculiar. Another patch of cretaceous 

 rocks occurs at St. Lucia Bay, in Zululand, resting un- 

 conformably on the Karoo strata. 



At the close of the Jurassic period, the Indo-oceanic 

 continent was submerged beneath a shallow cretaceous 

 sea, surrounded by coasts, covered with vegetation, 

 extending from India to Natal. At the close of this 

 epoch elevation commenced, and is probably still going 

 on, as raised beaches, coral reefs, and oyster banks may 

 be seen twelve feet above the sea. Through this action 

 the Port of Durban must inevitably be silted up, which 

 will be the fate of most of the ports on this coast, except 

 the large port of Delagoa Bay, which is naturally clean 

 swept by the north and south Mozambique current, which 

 has gradually hollowed out the Bay. 



Chas. E. De RANCE 



OUR ASTRONOMICAL COLUMN 

 Prizes of the Paris Academy.— At the annual 

 public sitting of the Academy of Sciences at Paris, last 

 week, the medal on the foundation of Lalande was 

 awarded to M . Stanislas Meunier for his researches on 

 the constitution of meteorites, which, in the opinion of 

 the Commission appointed for the consideration of claims, 

 have led to results that occasion surprise, but at the same 

 time appear justified by M. Meunier's investigations. 

 Astronomers had followed with interest the labours of 

 M. Daubree, who has contributed so much to estabhsh 



