724 



TRANSACTIONS OF SOCIETIES. 



South African Society of Civil Engineers. — Wednesday, May loth. 

 Prof. A. E. Snape, M.Sc, A.MT.C.E., M.R.San T.. President, in the chair.— 

 " Run-off at Dutoitspan " : W- Newdigate and Dr. J. R. Sutton. 

 Dutoitspan is one of the most important of tiie dams and vleis round 

 about Kimberley : the catchment area has been enlarged from time to 

 time, and ranged from 12.5 square miles in 1905 to 26 square miles in 

 1915. The percentage of run-off decreased from 7.7 in 1905 to 5.0 in 

 1915, the decrease being mainly due to the softer ground intersected by 

 the water courses at a distance from the pan. The more intense the rain- 

 fall, the greater was tlie run-off: thus, the run-off on 37 occasions on 

 which the rainfall was .5 in. or less averaged 3.1 per cent. The average was 

 7.7 on six occasions when the rainfall ranged from 1.51 to 2.00 inches, 

 and on one occasion a rainfall of 3.02 inches resulted in a 19. 6 per cent, 

 run-off. — "Construction and costs of reinforced concrete flume at Van 

 Wylisdorp, C.P." Full details were recorded of the construction of a 

 flume 60 feet long, in Anthus Kloof, a steep-sided water-course crossing 

 the canal of the Buffelsfontein Trrigation Scheme. The total cost of the 

 structure was fii.S. 



Wednesday, June 14th: Pn.f. A. E. Snape. M.Sc, .\.M.I.C.E., 

 M.R.San. I.. President, in the chair. — " Xotcs on Toivn-Plannini^ " : D. E. 

 liloyd-Davies. The author directed his remarks in particular to the 

 application of town-planning to the requirements of Greater Capetown. 

 In this connection the most urgently-needed regulations were indicated, 

 and a number of suggestions made for improvement of the general out- 

 line. — " Methods of uieasurin;^ zvork " : H. J. "Walker. In view of the 

 necessity for an engineer engaged on the construction of a railway line 

 to have at his command quick and accurate methods of measuring up 

 works, the author described the methods which he had adopted in respect 

 of banks and cuttings, classification of material, booking the measurements 

 and making calculations from the 'ield entries. 



Royal Society of South Afkua. — Wednesdnv. Mav 17th: A. M. 

 Wilson, M.D., B.S.. M.R.C.S., L.R.C-P.. Vice President, 'in the chair.— 

 " (Ecological Notes on the District of Manubie, Transkei" : W. T. 

 Saxton. The area comprises three chief plant formations, namely, wood- 

 land, park-like grassland, and sedge vegetation. The soil, a fine red brown 

 loam, is essentially uniform throughout the area. Xo marked differences 

 in climatic or edaphic factors distinguish the woodland from the grass 

 land, though these are of strikingly different appearance, and are separated 

 by a sharp boundary line. (a) "Note on the Radiations emitted by 

 degenerating tissues"; (b) "Note on the lonisation produced by degen- 

 erating nerve-muscle preparations" : J. S. van der Lingen. Organic 

 tissues may post mortem give rise to ionisation, which can be detected by 

 the discharge of an electroscope. On the second and third days after 

 death the discharge seems to attain its maximum. Radiation seems to be 

 given (jff which can affect .photographic plates. 



Wednesday, June 21st: L. A. Peringuey, D.Sc. F.E.S., F.Z.S , Pre- 

 sident, in the chair. — "Note on Protective Resemblance in post-larval 

 stages of some South African Fishes": Prof. J, D. F. Gilchrist. In Hemi- 

 ramplnis calabaricus the post-larva! stages of the fish have the size and 

 colour of fragments of weed, which are found in the waters which the 

 young fish frequent. When alarmed, the fish become rigid and float 

 about in an apparently inanimate condition. It is then difficult to dis- 

 tinguish them from the floating pieces of weed. In Klipfish (Clinus spp.) 

 the young are born alive, and they are of a clear glassy transparency diffi- 

 cult to detect in the water. The contour of the body is probably disguised 

 by a number of minute dark dots. — " On the .\forphology of tlie Female 

 Flower of Gnetum": Prof. H. H. W. Pearson. Diverse views recently 

 put forward on the structure of the flower of the Gnetales were discussed 

 in detail and comparerf with special reference to the author's own investi- 



