TRANSACTIONS OF SOCIETIES. 245 



equally revolutionary in character. The interest in chemical 

 discovery seems now to have finally shifted from the mere filling 

 up of blanks in the table oi the chemical elements to the problems 



of controlling the forces and velocities inherent in the ether of 

 space in such a manner as virtually to create something out of 

 nothing. 



TRANSACTIONS OF SOCIETIES. 



Chemical, Metallurgical and Mining Society of South Africa. — 

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

 chair. — " Atomic weights and a new theory of chemical affinity." : Dr. J. 

 Moir. The author had previously conceived (see Trans. Client. Soc, 

 1909, p. 1752; also Trans. Roy. Soc. S. Afr., vol. I, p. 413, and Rept. S.A. 

 Ass. Adv. Sc, 1909, p. 188) that the atom of each element is built up of 

 a large non-valent part, generally of integral atomic weight, and a small 

 fraction representing and proportional to the valency. The equivalent 

 weight of this affinity-element or proton ( fi) was assumed to be .009 of 

 that of the hydrogen atom. The author now proposes the conception that 

 every bond in the current chemical formulae represents a definite quantity 

 of an actual substance, and possesses weight, this weight being double of 

 that previously assumed, namely, .018 of the the weight of the hydrogen 

 alum. Numerous examples are given in support of the view advanced. — 

 " Some observations of the graphite deposits of Madagascar and Africa " : 

 E. R. Bawden, General observations were made regarding the occur- 

 rence of graphite in Madagascar, especially in the Province of Imernia, 

 and in Nyasaland, Rhodesia, and Angoniland. 



Saturday, January 18th : W. R. Dowling, M.I.M.M., President, in the 

 chair. — "A new method of precipitation by zinc"': J. S, MacArthur. 

 At the first introduction of the cyanide process in the metallurgy of gold 

 the recovery of the gold from the cyanide solution was effected by preci- 

 pitation by means of thread-like shavings of zinc. Except for the use of 

 zinc dust in the Merrill method, filiform zinc is still supreme, but its use 

 lias certain disadvantages. These the author overcomes by the use of small 

 zinc wafers. — " Cyaniding of gold and silver ore at Caveira Mine. Por- 

 tugal" : J. Hutton. Details were given of the practical application of 

 MacArthur's zinc wafer precipitation method. The advantages were : low 

 consumption of zinc, obviation of acid treatment, large saving in smelting 

 charges and in labour, and maintenance of an even zinc surface in the 

 boxes, free from channelling. 



Saturday, February 15th: W. R. Dowling. M.I.M.M., President in the 



chair. "The action of oxidizers in cyaniding": M. Green. Potassium 



permanganate is sometimes used on the Rand as an " aid to cyaniding," 

 but its action seems to be imperfectly understood. The permanganate is 

 added to the treatment charge, and then run on to the cyanide solution. 

 The author found that in the presence of much reducing matter the treat- 

 ment solution to which an excess of permanganate had been added would 

 not have a very pronounced effect so far as the oxidation of the reducer 

 is concerned. But where the quantity of reducing matter is small, such 

 a solution would in this connection be distinctly useful. If, however, the 

 value of the permanganate is supposed to lie in its yielding a solution 

 capable of dissolving the gold content of the charge more readily, the 

 author found the opposite to be the case. Another oxidizer of unkndVn 

 action is potassium ferricyanide. Its effect in causing the gold to dissolve 

 more rapidly in a solution of potassium cyanide does not appear to be due 

 to any reaction between the ferricyanide and the cyanide, but to some 

 process independent of the reduction of the former by the latter. It would 

 seem, therefore, that the assistance of oxidizers in the solution of gold is 

 of a secondare nature. 



