r 



Tlu^ Sedimentary Dejtosita of Soutliern Bhodesia. 'di^'o 



Equator. The axis of terrestrial symmetry through this pole 

 p.isses through the middle of Atric:i and of the Pacific Ocean. The 

 smallest circle svhicli will circumscribe Africa has its centre near this 

 pole, and within it the symmetry of the fractured African dome is 

 observable. Outside this comes a belt of seas, aud outside tliat 

 again the Pacitic belt of continents, the Antarctic, South America, 

 North America, Asia, and Australia. Mr. Jeans has concluded on 

 mathematical grounds that the ' pear-like shape of the earth ' might 

 have been possessed by it at the time of its consolidation ; and he 

 has suggested that Australia may represent the ' stalked end ' of 

 the • pear.' The author s observations would lead him to place 

 it in Africa, and to regard the Pacific as covering the ' broad end.' 



2. ' The Sedimentary Deposits of Southern Ehodesia.' By A, J. 

 C. :Molyneux. Esq., F.O.S. 



The greater portion of the area of Southern Ehodesia lies on 

 granite and gneiss, and on the schists and slates that contain the 

 auriierous veins worked in ancient times, and now being again 

 opened up on an extensive scale. The remaining area is on sand- 

 stone and other sedimentary beds, with coal-deposits, and regions 

 of volcanic rocks. To explain the deposition and order of these 

 sediments several sections are given ; one being along a line extending 

 from the Zambesi River on the north, through Bulawayo and the 

 central plateau, to the Limpopo River on the south, a distance of 

 over 400 miles. Another section, with remarks thereon, is copied. 

 by permission, from a report by Mr. C. J. Alford, E.G.S., on the 

 coal-bearing rocks of the Mafungibusi District, 



From Bulawayo fine sandstones continue for about 170 miles to 

 the north, when there is a sudden drop in the surface of the 

 country, caused by a lung line of cliffs of red sandstone, which 

 extends from the Zambesi Falls Road right across this portion of 

 Rhodesia, and finally merges into the Mafungibusi Hills far away 

 to the north-east. This is the great escarpment, formed by the 

 erosion of 400 feet of coarse grit with angular pebbles. To 

 the north-west of this escarpment, and running parallel with it, is a 

 long and narrow valley formed of soft shales which are known as 

 the Matobola Flats. Here the beds dip at 5^ south-eastward. Thus, 

 in proceeding farther to the north-west, underlying beds are re- 

 vealed, with a lower series of Coal-Measures containing seams of 

 workable coal. Below the Coal-Measures are quartzites and current- 

 bedded grits, which rise up and form the Sijarira Range, a flat 

 plateau 15 miles across. Its north-western side, however, is almosi 

 precipitous, and is capped by folds of quartzites. There is a drop 

 of 1100 feet in a few miles, and the rest of the country is almost 

 flat as far as the Zambesi River. To the west is the gorge of the 

 Lubu River, and it is there seen that the sediments rest upon 

 pegmatites and gneiss. 



Another section shows the contact of fine sediments and meta- 

 morphic rocks down the railway-line to the south-west past Sisi 



