April 30, 190X] 



NA TURE 



(ill 



form of magnetic separation was coming to the front. 

 For a long time the metfiod was confined to minerals that 

 were naturally or artificially magnetic in the everyday 

 acceptanie of that word, that is to say, were capable of 

 being attracted by an ordinary horse-shoe magnet. 

 Faraday had discovered so far back as 1845 that numerous 

 bodies, not magnetic in this ordinary sense, were neverthe- 

 less affected by powerful magnetic fields, but it was not 

 until 1896 that this principle was applied to the separation 

 of minerals by J. P. Wetherill ; he succeeded in separating 

 a series of minerals, all very feebly magnetic, from the 

 somewhat more feebly magnetic zinc oxide and other zinc 

 ores of New Jersey by the use of very powerful magnetic 

 fields, produced by means of electromagnets with wedge- 

 shaped pole-pieces, and since his original invention this 

 principle (the magnetic separation of non-magnetic material, 

 as it is sometimes called) has found an extended applica- 

 tion, one of the most recent being the magnetic concentra- 

 tion of specular haematite by the Edison deflection method, 

 using pole-pieces of the Wetherill type. Such separations 

 as that of wolfram from tinstone, of raw spathic ore 

 from zinc blende, of garnets from silver ore, which are 

 necessary before any rational metallurgical treatment of 

 the ores is possible, but which offer insuperable dit^iculties 

 to the ordinary methods of dressing, have been rendered 

 possible by the adoption of the Wetherill principle, and I 

 see no reason to doubt but that it will find still more 

 extended application in the future. I may point out that 

 no successful wet separator for feebly magnetic minerals 

 has yet been devised ; this is a problem presenting numerous 

 difficulties, but probably quite capable of solution, and at 

 the same time very well worth solving. 



Magnetic separation, though so comparatively novel, has 

 already been extensively applied, the largest installations 

 being naturally those for the treatment of iron ores. At 

 the present moment the output of high-grade magnetite 

 oncentrate, produced by this process, in Sweden cannot 

 fall far short of half a million tons per annum, and in 

 Norway active preparations are in progress for work on a 

 much larger scale at Dunderland, .Salangen, Ofoten, and 

 Sydvaranger, from which a yearly output of fully two 

 millions of tons of high-class iron concentrates is expected. 



Attempts to utilise other properties of minerals for their 

 separation may be said to belong wholly to the present 

 century. Thus Messrs. Blake and Morscher in iqoi, and 

 Mr. Xegreanu in 1002, have attempted to use electrostatic 

 methods, depending upon the variations in the electrification 

 of minerals due to their varying electric conductivities ; the 

 former of these two methods has been used with success 

 for the dressing of blende in the United States. 



Finally, the difference in surface tension has been 

 employed in Elmore's oil separation process, in the various 

 flotation processes, devised since the discovery of the prin- 

 ciple by C. V. Potter in igoi, and applied to the very 

 intractable zinc-lead ores of the Broken Hill district of 

 New South Wales, and finally in the Elmore vacuum 

 process. .All these processes seem to depend upon the 

 differential adhesive force, with which water, oil, or gas 

 cling to the surface of different minerals. These methods 

 are still in their infancy, and the underlying principles 

 cannot yet be said to be properly understood, but already 

 they promise to be of great value in recovering valuable 

 material from slimes that are not amenable to any other 

 mode of treatment, particularly for treating those intimate 

 mixtures of zinc blende and galena that have for so long 

 defied the ingenuity of both miners and metallurgists. 

 There are grounds for hoping that many of the problems 

 that have hitherto baffled the ore-dresser may be solved by 

 some application of these modern methods. 



SCIENCE AND INDUSTRY. 

 A SERIES of articles has appeared in the Rcvuc 

 ■^^ scientifiqiie (May 18 and July 13, 1907 ; February 22, 

 iqo8) comparing the teaching of technical chemistry in 

 France with the instruction given in the same subject in 

 other countries. The last article is of special interest as 

 presenting a French view of the relation subsisting between 

 science and industry in our own country. After de- 

 scribing in detail the excellent organisation of scientific 

 education in Germany, Belgium, and Switzerland, and 



NO. 2009. VOL. 77] 



emphasising the closeness of the union existing in these 

 countries between the manufacturer and the man of science, 

 it is stated that the system of technical education adopted 

 in England presents no feature worthy of commendation. 



The English manufacturer fails to realise how much he 

 may profit from the assistance of pure science ; — 

 " I'industriel anglais parait ou veut ignorer le chimiste 

 de carrifere qui vient k lui avec un bagage scientifique ; 

 son but 6tant de produire ' beaucoup et k bon marchd ' il 

 lui suffit quand il remarque un ouvrier plus intelligent et 

 plus, perfectible que ses camarades de I'envoyer aux ^coles 

 du soir, prendre un semblant d'instruction thi5orique et 

 cela sur la seule partie de la chimie qui peut int^resser son 

 m(5tier. " The many technical colleges under the control 

 of municipal authorities in this country do not aim at pro- 

 ducing highly trained " chemists " in the scientific sense 

 of the word, but waste their resources in providing even- 

 ing classes for workmen and artisans, and in imparting 

 the rudiments of science to boys from the primary schools. 



The university colleges, on the other hand, with the 

 exception of the Central Technical College, provide only a 

 training in pure chemistry. Until science and industry 

 become more intimately united in this country it is pre- 

 dicted that the technical schools will go on producing 

 merely good workmen and the universities men who are 

 unable to investigate practical problems or apply discoveries 

 made in the laboratory on an industrial scale. 



It would appear that the chemist is as little appreciated 

 in France as in our own country, and it is pertinently 

 asked whether this is not due to his lack of " general 

 culture " which prevents him from acquiring the broad 

 ideas necessary for the initiation or development of 

 important enterprises. The same question no doubt may 

 be asked of the chemists in this country, but whatever be 

 the answer there is no doubt that, for the proper develop- 

 ment of our industry in the near future, a closer union 

 between the industrialist and the chemist is vitally 

 necessarv. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Cambridge. — The board of managers of the Arnold 

 Gerstenberg studentship gives notice that a studentship will 

 be offered for competition in the Michaelmas term of igoq. 

 The competition will be open to men and women who have 

 obtained honours in part i. or part ii. of the natural 

 sciences tripos, apd whose first term of residence was not 

 earlier than the Michaelmas term of 1903. The student- 

 ship, which will be of the annual value of nearly 90Z., will 

 be tenable for two years. 



The Linacre lecture will be delivered by Dr. W. Osier, 

 F.R.S., on Wednesday, May 6, in the lecture-room of 

 anatomy and physiology, New Museums. The subject of 

 the lecture will be " Thomas Linacre, his Life and 

 Works." 



It is proposed to grant the use of the Senate House on 

 May 15 for a meeting of the members of the University 

 to be addressed by Mr. Haldane, Secretary of State for 

 War, in the explanation of his scheme in connection with 

 the training of officers for war. 



Part i. of the natural sciences tripos will commence on 

 Monday, May 25, and part ii. on Wednesday, May 27. 

 The number of entries for the two parts is about two 

 hundred and twenty. 



Glasgow. — Among the recipients of the honorary degree 

 of Doctor of Laws on Commemoration Day, .April 22, 

 were several distinguished by their scientific attainments. 

 In the afternoon a portrait of Prof. M'Kendrick was pre- 

 sented to the University, with the sum of 450/. for the 

 equipment of a laboratory of experimental psychology in 

 the new physiological buildings, in honour of Prof. 

 .M'Kendrick's thirty years' service to the University as 

 professor of physiology. In presenting the representatives 

 of science for the degrees. Prof. Gloag, dean of the faculty 

 of law, made the following references to their work : — 



Mr. G. T. Beilbv, F.R.S., chairman of the governors 

 of the Glasgow and West of Scotland Technical College. — 

 The present head of the Glasgow and West of Scotland 

 Technical College, who is a Fellow of the Royal Society, 



