Page:South African Geology - Schwarz - 1912.djvu/130

 Bain, a road surveyor like William Smith. An account of Bain's work, together with the first map of South Africa, was published in the Transactions of the Geological Society of London in 1856, although the material was forwarded from South Africa in 1852. The next map of South Africa was published in 1872 by E. J. Dunn, who was actually the first Government Geologist, and subsequent editions appeared in 1875 and 1887. In 1896 the geological survey of Cape Colony was instituted, and shortly afterwards the surveys of the Transvaal and Natal, and recently the geological surveys of German South-west Africa and Rhodesia. The mass of information is now enormous, but the country is so vast that it is very difficult to join up the work in different regions and weld the whole into an understandable scheme.

In dealing with rock strata, directly one finds a fossil, there is a definite means of establishing the age of the rock, as determined by the European scale of superposition of rocks. In South Africa, however, most of the rocks are unfossiliferous, and comparison by mineral structure is uncertain, therefore there is great confusion in the nomenclature. Mostly geological surveyors in studying any one district find a series of beds which have certain characteristics, and these are given local names. In an adjoining district, other rocks occur with other characteristics, and new local names are given, and so on, till the geology of the unfossiliferous rocks of South Africa has become a mere catalogue of names. Certain broad principles, however, have emerged, and if the student is mystified by the prolixity of systems in the unfossiliferous rocks, he must console himself with the fact that they are pioneer attempts at the understanding of the country, and that the time has not elapsed, nor