64 TRANSACTIONS OF SOCTETrES. 



/ Thursdaj-, September 18th: Prof. VV. Buchanan, B.Sc, A.R.C.S., 

 M.I.E.E.. Vice-President, in the chair: — "Notes on electric furnaces, with 

 special reference to an induction furnace " : Dr. W. Glucksmann. 



After referring shortly to the three dififerent classes of arc furnaces and 

 to tlie resistance furnaces in use at present, the author proceeded to 

 describe in detail Gassie's induction furnace recently installed at St. Jacques, 

 France, and concluded with some general remarks on the efficiency of 

 electric furnaces. 



S.A. Institltion of Knginkeks. — Friday, May i6th : W. Calder, Vice- 

 President, in the chair. — " The manufacture of cement :" E. Davidson. 

 The properties and applications of Portland cement were briefly sketched,, 

 and details were given of improvements in the !)urning of the raw material 

 and with regard to the preparation nf the latter for the kiln. — 

 "Notes nn the theory of centrifugal pumps and ventilating fans": 

 A. S. Ostreicher. A teclmical paper in which the subject was treated 



mathematically, with geometrical ilhistrations. 



(Kimberley Branch), Thursday, May 26th: J. llarbottle, Chairman of 

 the Branch, in the chair. — -" Central Power station working, with special 

 reference to De Beers Central Power Station :" G. M. Robertson. A 

 fully-detailed description of the equi|)ment and work (^i the Central Power 

 Station. 



Saturday. August 16th :W. Calder. President, in the chair. — Presidential 

 address : \V. Calder. Reference wa^ made to some of the problems in 

 connection with the mining industry that are still awaiting solution. 

 Amongst these are the question of cheaper working costs, the economic 

 centralisation of mining work, the sanitary cr-nditions underground, the 

 instability resulting from large worked-out open spaces, the need of 

 systematic underground sorting, the air consumption of rock drills, the 

 conservation and use of water, and the electrification of mining plants. 



ChemicaLj ^Ietallukcicai. AXi) Mining Sociktv of Soi-th Africa. — 

 Saturdax. May 17th: \\^ R. Dowling. M.I.M.M., President, in the chair. — 

 " Vacuum filtration at the Victoria Mill of the Waihi Gold Mining 

 Company, New Zealand": W. Macdonald. .\ general description was 

 given of the plant, which has Iteen in i>peration since the lieginning of 

 1908. The vacuum pumps, which are of the double acting type, are eight 

 in number, the motive power Ijcing a 200 h.p. Crossley gas engine. An 

 outline was added showing the general conditions of the milling and 

 treatment plant governing the production and character of the slime pulp. 

 An account of the routine work of the plant was given, and the efficiency 

 of the filtration process and of the extraction and recovery of the last 

 traces of gold and silver bearing solution was di.scussed. 



Saturday, June 21st: W. R. Dowling. M.I.M.M., President, in the 

 chair — ."Notes on the assay of Mine Samples" R. Dures. The assay 

 of samples sent up from working faces of mines was discussed, and some 

 of the errors occurring in the manipulation of these assays were 

 pointed out. Details were given of a variety of tests showing the effects on 

 assay results of (i) coarse and fine grinding, (j) varying the amounts of 

 charcoal and of other components of the charge, (3) careful cleaning of 

 the beads before weighing, (4) duplicating the assays, (5) inadequate 

 heating of the muffle, (6) cupelling tlie gold with silver. 



South African Society of Civil Engineer.s. — Wednesday, June nth: 

 F. E. Kanthack, M.I.C.E., President, in the chair.. — " New station yards at 

 Germiston and Braamfontein '" : H. H. Elliott. Works in connection with 

 the provision of new railway stations and yards at Germiston and Braam- 

 fontein have been recently completed, and as the alterations and additions 

 were on a scale larger than any that had been previously undertaken at 

 any station in the Union, particulars of the works were given. 



Wednesday. July pth : T. W. Perry, M.I.Mech.E., in the chair.— 

 " Roads in their relation to the development of the country " : W. Craig. 

 The author's remarks were virtually confined to the Cape Province, in 



