September 4, 1890] 



NATURE 



437 



The application of electric traction to water-traffic, first suc- 

 cessfully demonstrated in 1883, is receiving gradual development, 

 as illustrated by the considerable number of pleasure-boats which 

 may now be seen on the Upper Thames during the boating 

 season, and in connection with which Prof. George Forbes 

 proposed, at our meeting last year, that stations for charging the 

 requisite cells, through the agency of water-power, should be 

 established at the many weirs along the river, so as to provide 

 convenient electric coaling stations for the river pleasure- fleet. 



Electrically-transmitted energy was first applied in Germany 

 to haulage work in mines by the firm of Siemens some years ago, 

 and great progress has since been achieved herein on the Contin- 

 ent and in America. Comparatively little has been accomplished 

 in this direction in England ; but it is very interesting to note, on 

 the present occasion, that the first successful practical application 

 of electricity in this country to pumping and underground 

 haulage-work was made in 1887, in this neighbourhood, at the 

 St. John's Colliery, at Normanton, where an extensive installa- 

 tion, carried out by Mr. Immisch, so well known in connection 

 with electric launches, is furnishing very satisfactory results in 

 point of economy and efficiency. The gigantic installations 

 existing for the same purposes in Nevada and California afford 

 remarkable illustrations of the work to be accomplished in the 

 future by electrically-transmitted energy. 



Among the many subjects of importance studied by Joule with 

 the originality and thoroughness characteristic of his work, was 

 the application of voltaic electricity to the welding and fusion of 

 metals. Thirty-four years ago he published a most suggestive 

 paper on the subject, in which, after dealing with the difficulties 

 attending the operation of welding, and of the interference of 

 films of oxide, formed upon the highly heated iron surfaces, with 

 the production of perfect welds either under the hammer or by 

 the methods of pressure (of which he then predicted the applica- 

 tion to large masses of forged iron), he refers to the possibility 

 of applying the calorific agency of the electric current to the 

 welding of metals, and describes an operation witnessed by 

 him in the laboratory of his fellow-labourer, Thomson, of 

 fusing together a bundle of iron wires by transmitting through 

 them, when embedded in charcoal, a powerful voltaic current. 

 Joule afterwards succeeded in fusing together a number of iron 

 wires with the current of a Daniell battery, and in welding 

 togetherwiresofbrass and steel,platinum and iron, &c. In discuss- 

 ing the question of the amount of zinc consumed in a battery for 

 raising a given amount of iron to the temperature of fusion, he 

 points out that the same object would probably be more economi- 

 cally attained by the use of a magneto-electric machine, which 

 would allow the heat to be provided by the expenditure of 

 mechanical force, developed in the first instance by the expendi- 

 ture of heat ; and he indicates the possibility of arranging 

 machinery to produce electric currents which shall evolve one- 

 tenth of the total heat due to the combustion of the coal used, 

 so that 5000 grains of coal applied through that agency would 

 suffice for the fusion of one pound of iron. The successful 

 practical realization of Joule's predictions in regard to the appli- 

 cation of electric currents, thus developed, to the welding of 

 iron and steel, and to analogous operations, through the agency 

 of ihe efficient machines devised by Prof. Elihu Thomson, was 

 demonstrated to the members of the Association by Prof. Ayrton 

 at Bath two years ago, and was shown upon a larger scale to 

 visitors at the Paris Exhibition last year, and recently to highly 

 interested audiences in London by our late President, Sir 

 Frederick Bramwell. The latter demonstrated that the produc- 

 tion of iron-welds by means of the Thomson machines was 

 accomplished nearly twice as rapidly as by expert craftsmen ; the 

 perfection of the welds being proved by the fact that the strength 

 of bars broken by tensile strains at the welds themselves was 

 about 92 per cent, of the strength of the solid metal. At the 

 Crewe Works Mr. Webb is successfully applying one of these 

 machines to a variety of welding-work. The rapidity with which 

 masses of metal of various dimensions are raised in those machines 

 to welding heat is quite under control ; the heat is applied with- 

 out the advent of any impurities, as from fuel, and the speed of 

 execution of the welding operation reduces to a minimum 

 the time during which the heated surfaces are liable to oxidize. 

 With such practical advantages as these, this system of electric 

 welding bids fair to receive many useful applications. 



Another very simple system of electric welding, especially 

 applicable to thin iron and steel sheets, hoops, &c., has been 

 cotemporaneously elaborated in Russia by Dr. Bernados, and is i 

 already being extensively used. The required heat at the surfaces 



NO, 1088. VOL. 42] 



to be welded is developed by connecting the metal with the 

 negative pole of the dynamo-machine, or a battery of accumula- 

 tors, the circuit being completed by applying a carbon electrode 

 to the parts to be heated ; the reducing power of the carbon is 

 said to preserve the heated metal surfaces from oxidation during 

 the very brief period of heating. This mode of operation 

 appears to have been practised upon a small scale, some 

 years ago, by Sir William Siemens, to whom we also owe the 

 first attempt to practically apply electric energy to the smelting 

 of metals. 



In his address in 1882 he referred to some results attained 

 with his small electrical furnace, and pointed out that, although 

 electric energy could, obviously, not compete economically with 

 the direct combustion of fuel for the production of ordinary 

 degrees of heat, the electric furnace would probably receive ad- 

 vantageous application for the attainment of temperatures ex- 

 ceeding the limits (about 1800° C.) beyond which combustion 

 was known to proceed very sluggishly. This prediction appears 

 to have been already realized through the important labours of 

 Messrs. Cowles, who some years ago attacked the subject of the 

 application of electricity to the achievement of metallurgic 

 operations with the characteristic vigour and fertility of resource 

 of our Transatlantic brethren. After very promising preliminary 

 experiments, they succeeded, in 1885, at Cleveland, Ohio, in 

 maturing a method of operation for the production of aluminium- 

 bronze, ferro-aluminium, and silicium-bronze, with results so 

 satisfactory as to lead to the erection of extensive works at 

 Lockport, N.Y., where three dynamo-machines, each supply- 

 ing a current of about 3000 Amperes, are worked by water- 

 power, through the agency of turbines, each of 500 horse-power, 

 eighteen electric furnaces being now in operation for the produc- 

 tion of aluminium alloys. These achievements have led to the 

 establishment of similar works in North Staffordshire, where a 

 gigantic dynamo-machine has been erected, furnishing a current 

 of 5000 Amperes, with an E.M.F. of 50 to 60 volts. The 

 arrangements of the electrodes in the furnaces, the preparation 

 i)f the furnace-charges (consisting of mixtures of aluminium- 

 ore with charcoal and with the particular granulated metal 

 with which the aluminium is to become alloyed at the 

 moment of its elimination from the ore) ; the appliances for 

 securing safety in dealing with the current from the huge dynamo- 

 machine, and many other details connected with this new 

 system of metallurgic work, possess great interest. Various 

 valuable copper- and aluminium-alloys are now produced by 

 alloying copper itself with definite proportions of the copper- 

 alloy, very rich in aluminium, which is the product of the 

 electric furnace. The rapid production in large quantities of 

 ferro-aluminium — which presents the aluminium in a form suit- 

 able for addition in definite proportions to fluid cast-iron and 

 steel — is another useful outcome of the practical development of 

 the electric furnace by Messrs. Cowles. 



The electric process of producing aluminium-alloys has, how- 

 ever, to compete commercially with their manufacture by adding 

 to metals, or alloys, pure aluminium produced by processes 

 based upon the method originally indicated by Oersted in 1824, 

 successfully carried out by Wohler three years later, and de- 

 veloped into a practical process by H. Ste. Claire Deville in 

 1854— namely, by eliminating aluminium from the double 

 chloride of sodium and aluminium in the presence of a fluoride, 

 through the agency of sodium. An analogous process, indicated 

 in the first instance by H. Rose — namely, the corresponding 

 action of sodium upon the mineral cryolite, a double fluoride of 

 aluminium and sodium — has also been recently developed at 

 Newcastle, where the first of these methods was applied, upon 

 a somewhat considerable scale, in i860, by Sir Lowthian Bell, 

 but did not then become a commercial success, mainly owing to 

 the costliness of the requisite sodium. As the cost of this metal 

 chiefly determines the price of the aluminium, technical chemists 

 have devoted their best energies to the perfection and simplifica- 

 tion of methods for its production, and the success which has 

 culminated in the admirable Castner process constitutes one of 

 the most interesting of recent illustrations of the progress made 

 in technical chemistry, consequent upon the happy blending of 

 chemical with mechanical science, through the labours of the 

 chemical engineer. 



Those who, like myself, remember how, between forty and 

 fifty years ago, a few grains of sodium and potassium were trea- 

 sured up by the chemist, and used with parsimonious care in an 

 occasional lecture experiment, cannot tire of feasting their eyes 

 on the stores of sodium-ingots to be seen at Oldbury as the 



