l8o NEW BOOKS. 



Eastern Districts of the Cape Province, with a discussion on the .magnetic 

 states of these regions. — "Action of radium salts on glass " : Prof. W. A. D. 

 Rudge. As the result of experiments carried on for three years with 

 radium salts sealed up in glass tubes, sections of which were afterwards 

 cut and microscopically examined, in order to ascertain the depth to 

 which colouration had penetrated, a zonal structure was observed, with 

 abrupt changes in depth of colouration at the junction of successive zones. 

 It was concluded that the colouration was due to ^ and y rays, as well 

 as to a particles and emanation. — "A new species of incscmhryanthcinum 

 from the Transvaal; and notes on the genus Ficus": J. Burtt-Davy. 



South African Institute of Engineers. — Saturday, October 14th: Mr. 

 F. H. Davis, President, in the chair. — "The manufacture of turbines as a 

 future industry " : A. S. Ostreicher. The author expressed the con- 

 viction that water turbines of a moderate size, up to six feet in diameter, 

 would be the first engineering specialities to be successfully manufactured 

 in South Africa. He proceeded to describe the manufacture of a modern 

 Francis turbine, illustrating his remarks by means of diagrams, and re- 

 ferring specially to the attainment of high efficiency and the methods of 

 speed regiUation. 



Geological Society of South Africa. — Monday, October i6th. Dr. 

 E. T. Mellor, President, in the chair. — "Xenoliths in gabbro, near Belfast, 

 Transvaal " : J. P. Johnson. Attention was drawn to patches of 

 abnorn;al composition occurring in an otherwise normally homogeneous 

 gabbro of considerable extent, on the farm Wintershoek, and having the 

 appearance of altered inclusions. The most remarkable of these xenoliths 

 consist of a coarse-grained rock, bearing a resemblance to the ec'.ogites 

 of the diamond pipes : it is an evenly granular aggregate of garnet, quartz, 

 and some semi-opaque greenisli mineral with a well-developed cleavage. 



ADDRESSES WANTED. 



The Assistant General Secretary (P.O- Box 1497, Cape Town) 

 would be glad to receive the correct addresses of the following members, 

 whose last-known addresses are given below: — 



Aspland, C- Hatton, Witwatersrand Deep, Ltd., P-O- Box 5, Knight's, 



Transvaal- 

 Barton, Ernest Mortlock, Director of Works Department, Simons- 

 town, Cape- 

 Bay, Dr- B-, P-O- Box 5513, Johannesburg- 

 Bell, W- Reid, M-I-C-E-, F-R- Met- Soc-, M-I-E-S-, P.O, Box 2263, 



Johannesburg- 

 Boulton, H- C-, c/o Messrs- Pauling & Co-, Ltd-, Broken Hill, 



Rhodesia- 

 Brown, W- B-, c/o Engineer-in-Chief, S-A- Railways, Cape Town- 

 Champion, Ivor Edward, P-O- Roberts Heights, Pretoria. 

 Crockett, John, 10, Transvaal Bank Buildings, Johannesburg- 

 Dickie, Andrew, 475, Currie Road- Durban, Natal- 

 Leech, Dr- J- R-, 4th Avenue, Melville, Johannesburg- 

 Macfarlane, Donald, M-I-C-E-, H-M- Naval Dockyard, Simonstown, 



Cape- 

 Mirrilees, W- J-, 9, London Chambers, Durban- 

 Nichol, Thomas Thompson, P-O- Box 34, Springs, Transvaal. 

 Nicholas, W- H-, Durban High School, Durban. Natal. 

 Nicholson, J. Greg, Leliefontein, Government School, P.O. Carolina, 



Transvaal. 

 Petersen, H. T., P-O- Box 5, Cleveland, Transvaal. 

 Preston, James, 89, Arnold Road, Observatory, near Cape Town. 

 Southwell, Miss Jessie, 270, Visagie Street, Pretoria. 

 Van Oordt, J. F., Harrismith, O.F.S. 



