I30 TRANSACTIONS OF SOCIETIES. 



Saturda}', Xovembcr 8th: ^Ir. W. Calder, President, in the chair. — 

 " Ventilation of Mines " : W. Pile. The author insisted on the absohite 

 ntcessity that a free and continuous supply of fresh air should be equally 

 and efficiently distributed throughout each mine. Me compared the 

 " naturally " with the " mechanically " \entilated mines, and with those 

 where a combination of " natural " ventilation with fans was employed. 

 " Natural " ventilation he regarded as unreliable, and as the flow of air 

 can be more easily induced than forced, fans would be more efficient if 

 placed at the top of the upcast shafts. The system of blowers is not com- 

 mended, as the forcing of air down a mine would raise fts temperature, 

 while the air itself, coming from the travelling roads would be impure 

 and heated. The construction of large airways was suggested, and the 

 constitution of a Ventilation Board, composed of practical men, in respect 

 of each mining district. 



Geological Society of South Africa. — Monday, November 17th: Dr. 

 E. T. Mellor in the chair. — " Notes on a form of black diamond from the 

 Premier Mine " : D. P. Macdonald. Specimens of this rather peculiar 

 variety of diamond have been found distributed throughout the part of 

 the pipe now being worked, and were not confined to any one locality in 

 the mine. The largest piece weighs 104 carats. The physical characters 

 of the diamond were described, as well as the efTects noticed on heating 

 fragments and powder under different conditions. The appearances. Iwth 

 of the diamond powder and of the sections under the microscope were 

 described: throughout the specimens there is transparent carbon, but in 

 mass tlie diamond is opaque, because of tlie density of tlie opaque particles 

 scattered throughout its substance. Tn the muffle furnace the diamonds 

 yielded a yellowish-brown ash, to the extent of 3 per cent. This ash was 

 physically, microscopically, and cliemically examined. The results observed 

 were detailed, and tlie nature of the black carbon enclosed in the diamond 

 discussed. 



Rhodesia Scientific Association. — Wednesday. December 24th: IVIr. 

 H. B. Maufe, B.A., F.G.S., in the chair. — " The Mosquito Plague, and the 

 necessity for eliminating the nuisance from the town " : D. E. H. Strong. 

 An account of the life-histon,- of the mosquito was given, and the best 

 means of securing its destruction discussed. 



XKW ROOKS. 



Fraser, Donald. — Wiuniiif; a primitive people: Sixteen years' work 

 aiiioiic: the warlike tribe of the Ngoni and the Senga and Timbuka 

 peoples of Central Africa. 8 X 5 in., pp. 320. Maps and illus. 

 London : Seeley, Service & Co., 1914. 5s. 



lYorsfold, S. N. Basil. — TIic reconstruction of the new Colonies under 

 Lord Milliter. 8vo. (2 vols.), pp. vi, 376, j\2.g. London: Kegan 

 Paul. Trench, Triibner & Co., 1913. 48 oz. 25s. 



Markham, Violet R. — The South African Scene. 8vo., pp. vii, 450. 

 London : Smitli, Elder & Co., 1913. 24 oz. 7s. 6d. 



Tremearne, Major A. J. N. —.9o;n^ Austral-African notes and anec- 

 dotes. 9 X 5} in. pp. xii, 215. Illuis. London: Bate, Sons & 

 Danielsson, 191,3. 7s. 6d. 



Macdonald, Dr, W.— T/ie conquest of the desert. 9 X Si^ in.-, pp. xii. 

 197. Maps and illus. London : T. Werner Laurie, 1913. 7?. 6d. 



