ri< vnsa< noNS of societies. 53 



purpose. The conditions of living and pay did not seem unsatisfactory. 

 Facilities were provided for technical training, but not as fully taken ad- 

 vantage of as might be expected. The institution of compulsory attendance 

 cf learners and apprentice- at technical classes was suggested.— " Mine 

 tributing in Rhodesia" : W. Anderson. An account of the manner of 

 letting small mine- on tribute in vogue in Rhodesia, together with a descrip- 

 tion of the usual equipment and method of development and working 

 Operations and conditions of Mich mines. 



Saturday. July jotli : .Mr. W. R. Dowling, M.I.M.M., President, in 

 the chair. — Presidential address: W. 1\. Dowling. The address dealt with 

 the work done and influence exerted by the Society in the past, and par- 

 ticularly during the past year. — " Notes on the cyaniding of concentrate'' : 

 R. Linton. An account of a series of tests made in order to determine 

 the advantage or otherwise of cyaniding raw concentrate instead of trans- 

 porting it to a customs smelter. The use of lead acetate appeared to be 

 of no benefit in preventing the destruction of cyanide, although a small 

 amount served to keep the solutions clear. 



South African Institution of Engineers. — Saturday, April 20th: 

 Mr. J. A. Yule, Vice-President, in the chair. — "The Cascade single 

 and multi-speed motor " : M. J. Williams-Ellis. A brief account 

 was first given of early work carried out upon Cascade con- 

 struction by Silvanus Thompson and others, after which the author 

 proceeded to describe the single and the double type of Cascade induction 

 motor, and it- adaptation to mine and general work. References were also 

 made to other multi-speed types of motors. — "The margin of safety re- 

 quired for man haulage at great depths " : R. B. Greer. The author 

 pointed out that the present margin of safety required by Government 

 regulations in the Transvaal for man haulage was generally adopted as 

 far back as 1877, when winding at great depths was not the common 

 practice that it is now. He considered it advisable for the Government 

 to modify the present margin of safety by a sliding scale after a depth of 

 2.500 or 3,000 feet. 



Saturday. May 4th: Mr. F. If. Davis, President, in the chair. — "The 

 commercial economy of turbine pumps " : F. zur Nedden and FT. R. 

 Maxwell. A comprehensive account of the theory and characteristics 

 of turbine pumps, and of the means to he adopted in order to ensure their 

 efficient and economic working. 



Saturday, July 13th : Mr. J. A. Yule, President, in the chair.— Presi- 

 dential address : J. A. Yule. Attention was drawn to various efforts for 

 economising labour in connection with the machinery used on the Rand 

 Mine-, both in respect of surface plants as well as of underground opera- 

 tions. The desirability was also pointed out, in view of the scarcity of 

 agricultural labour, of inaugurating, under the Minister of Agriculture. 

 a special department equipped with the most efficient farming implements. 

 portable traction machinery, and deep boring appliances, for the purpose of 

 being hired out to agriculturists at low rates. 



Saturday, August roth: Mr. J. A. Yule, President, in the chair. — "The 

 execution of plans and drawings": Dr. W. Glucksman. The author 

 held that the preliminary study of every object to be constructed should 

 comprise four stages ; ( r ) a forestudy in freehand, accompanied by an 

 explanatory memoir, (2) a study in concert, being a development of the 

 forestudy, geometrically true and constructed by means of drawing instru- 

 ments. (3) a study of details, including a study of the nature and quality 

 of the materials of construction, with all dimensions marked, and (4) a 

 study of execution, including such points as the fit of moving or working 

 parts, and bending or expansion. 



Geological Society of South Africa. — Monday. May 13th: Mr. H. 

 Kynaston, B.A., F.G.S., in the chair. — " Iridosmine from the Xew Rietfon- 

 tein Mines; its analysis, occurrence, and genesis": C. B. Horwoor" . 

 tridi -mine occurs in minute quantities, associated with the gold in the 

 mines, which are situated about nine miles east of Johanncsburir. Spectro- 

 examinaticn showed strong lines of osmium and ruthenium, hut 



