28 i'i;ksii)Kxt"s aodi^kss. 



(55) Passarge in " Die Kalahari," p. 657, refers to the lack of sand 

 deserts in the Kalahari and suggests that the irregularly undulating sand 

 veld in certain areas seen by him are the remains of old tracts of dunes 

 formed during a hypothetical " Interpluvialzeit." The observations 

 recorded in Ann. Rep! Geol. Com. for 1907, pp. 92-95, are in agreement 

 with the old age of the present surface of the sand, for it was evident 

 that " the existing long and short sand dunes have long been in their 

 present positions." 



(56) Instances are given in " Geology of Dam Construction," by A. L. 

 du Toit, Proceedings of the S.A. Society of Civil Engineers, 1922, pp. 

 27-32, where he attributes the present entrenchment of the river beds in 

 the alluvial deposits to the present greater rainfall following a period of 

 aridity, which was preceded by a wet period. These instances are not 

 quite of the same import as the partially filled-in kloofs of the Transvaal 

 mentioned on a previous page, for the latter cannot be attributed to change 

 by tilting or erosion, the distances involved being too short. 



(57) The deposition of silt through the flattening of the grade of a 

 river by erosion is well illustrated by rivers whicli leave soft rocks and 

 pass over hard ones, such as the Hartebeest in Kenhardt, which, with 

 its affluents the Zak and Olifant's Vley Rivers, passes from the soft Ecca 

 and Dwyka beds over dolerite and gneiss; or the Dwyka and Gamka Rivers 

 of the Karroo, which have cut plains on the comparatively soft Karroo 

 beds and have covered them with alluvium behind the hard quartzitea 

 of the Cape System. 



(58) The results of boring in the pan and their full discussion, together 

 with a detailed account of the geology and economic aspects of the pan 

 are contained in a Memoir, " The Pretoria Salt Pan, or Soda Caldera," 

 by Dr. P. A. Wagner, which will be published shortly. A short study of 

 the pan by that geologist is contained in his presidential address to the 

 Geol. Soc. of S.A. printed in the Proceedings, vol. XX, for 1917, and he 

 gave some further details in " Note on the Volcanic Origin of the Salt 

 Pan, etc.," Trans. Geol. Soc. S.A., vol. XXIII, 1920, p. 52. 



(59) Ann. Rep. Geol. Com. for 1907, pp. 107 and 109. Also, in Hav, 

 Ann. Rep. Geol. Com. for 1906, p. 131. 



(60) " A Note on Some Fossils from the Vaal River Gravels," by 

 S. H. Haughton, Trans. Geol. Soc. S.A., vol. XXIV, 1921, pp. 11-16, where 

 references to earlier finds are given; R. Broom, Annals of the S.A. Museum, 

 vol. VII, 1909, pp. 279-282, and vol. XII, pp. 13-16. 



(61) Ann. Rep. Geol. Com. for 1905, pp. 293-4. 



(62) " Journal of Researches," London, 1839, pp. 99-104. W. J. 

 Burchell, " Travels," vol. II, 1824, p. 207, " As far as I am able to judge, 

 there is no region in any quarter of the world which can hold comparison 

 with Southern Africa in number of large animals." Burchell also 

 emphasized the weight of each animal, and gave it as his opinion that 

 the average weight of the South African species would be found to be 

 higher than that of species in other countries. 



(63) E. H. L. Schwarz, " The Kalahari, or Thirst Land Redemption," 

 p. 5. On the next page Prof. Schwarz says " it is incredible that the 

 country (near Bloemfontein) could have supported such vast quantities of 

 animals (to yield 6,000 head of game to a shooting party in one day) 

 unless the climate and vegetation were very different from what they are 

 to-day." I do not find it incredible, especially after seeing trek buck. 

 In April, 1916, east of Karas Berg I passed a herd of springbok at a 

 distance of some 800 yards ; they subtended an angle of 45°, and I could 

 not see a gap in the line nor the width of the herd in the line of sight ; 

 the buck overlapped. There were probably more than 6,000 buck in that 

 herd, and the district is not a luxuriant one; one may easily travel 30 

 miles between waters, and farm houses are very far apart ; the country 

 near Bloemfontein is generally much better covered with grass, and we 

 do not know whether arrangements were made for beating up game on 

 the occasion of Prince Alfred's visit to Bain's Vley. Such herds as I saw 

 near Karas Berg are doomed ; they are incompatible with farming, and 



