HISTORICAL GEOLOGY 105 



siastic Scotch writer, Sir Andrew Ramsay, in 1855 

 described certain late Paleozoic conglomerates of middle 

 England, which he said were of glacial origin, but his 

 evidence, though never completely gainsaid, has not been 

 generally accepted. In the following year, an English- 

 man, Doctor W. T. Blanford, said that the Talchir con- 

 glomerates of central and southern India were of glacial 

 origin, and since then the evidence for a Permian glacial 

 climate has been steadily accumulating. Africa is the 

 land of tillites, and here in 1870 Sutherland pointed out 

 that the conglomerates of the Karroo formation were of 

 glacial origin. Australia also has Permian glacial 

 deposits, and they are known widely in eastern Brazil, 

 the Falkland Islands, the vicinity of Boston, and else- 

 where. So convincing is this testimony that all geolo- 

 gists are now ready to accept the conclusion that a 

 glacial climate was as wide-spread in early Permian time 

 as was that of the Pleistocene. 1 



In South Africa, beneath the marine Lower Devonian, 

 occurs the Table Mountain series, 5000 feet thick. The 

 series is essentially one of quartzites, with zones of shales 

 or slates and with striated pebbles up to 15 inches long. 

 The latter occur in pockets and seem to be of glacial origin. 

 There are here no typical tillites, and no striated under- 

 grounds have so far been found. While the evidence of 

 the deposits appears to favor the conclusion that the 

 Table Mountain strata were laid down in cold waters with 

 floating ice derived from glaciers, it is as yet impossible 

 to assign these sediments a definite geologic age. They 

 are certainly not younger than the Lower Devonian, but 

 it has not yet been established to what period of the 

 early Paleozoic they belong. 



In southeastern Australia occur tillites of wide distri- 

 bution that lie conformably beneath, but sharply sep- 

 arated from the fossiliferous marine Lower Cambrian 

 strata. David (1907), Howchin (1908), and other Aus- 

 tralian geologists think they are of Cambrian time, but 

 to the writer they seem more probably late Proterozoic 

 in age. In arctic Norway Reusch discovered unmistak- 

 able tillites in 1891, and this occurrence was confirmed by 

 Strahan in 1897. It is not yet certainly known what 

 their age is, but it appears to be late Proterozoic rather 



