478 



NATURE 



[September 15, 1892 



6. Wertheimer. — The elimination of pigments by the liver, 



7. JLoew, — The distinction between the "active" and the 

 " passive " albuminous material of plants. 



8. Sherrington. — The varieties of leucocytes. 



B. Demonstratiotis. 



1. Chauveau. — The changes in mammalian endocardiac pres- 

 sure as recorded by the tambour and air transmission method. 

 (This classical experiment formed the main part of the after- 

 noon's work.) 



2. Grehant.— («) Absorption of carbonic oxide by living or- 

 ganisms. 



3. Grehant and Martin. — On the physiological effects of 

 opium. 



4. Wedensky. — Demonstrations with the telephone upon 

 nerve excitation and upon voluntary muscular contraction in 

 man. 



5. Zwaardemaker. — The mechanism of smell. 



Wednesday, August 3 r.— Presidents : Prof. Wedensky 

 (St. Petersburg), Prof. Grigorescu (Bucharest). 



A. Communications. 



1. Cybulski.- The use of the condenser for the excitation of 

 muscles and of nerves. 



2. Hedon. — The effect of removal and of transplantation of 

 the pancreas upon the production of diabetes mellitus. 



3. Gotch. — The increased excitability of nerve and of muscle 

 occasioned by low temperature. 



4. Burch.— (a) The apparatus for photographing the move- 



ments of the capillary electrometer. 

 {b) The method of analyzing the electrometer 

 curves obtained by the photographic method. 



5. Burdon Sanderson. — The electrical changes in muscle as 

 shown by the capillary electrometer. 



6. Fredericq.^ — Autotomy in crabs. 



7. Jacobi. — The muscular sense. 



8. Bayliss. — The functions of the depressor nerve. 



9. Doyon. — Tetanus. 



10. Wedensky.— The impossibility of causing fatigue in motor 

 nerves. 



11. Verworn. — The effect of galvanic currents on simple living 

 organisms'. 



12. Moussu. — The functions of the thyroid body. 



13. Slosse. — {a) The functions of the thyroid body ; 



\b) Autopsy of a case of thyrodectoniy in the dog. 



14. Kaufman. — The intra-muscular circulation. 



15. De Boeck. — The effects of partial ablation of the cerebrum 

 immediately after birth. 



B. Demonstrations. 



1. Waller. — The discharge of heat from the muscles of man. 



2. Gotch, — The increased excitability of the sciatic nerve of 

 the cat produced by low temperature. 



3. Grigorescu.— Action of certain poisons upon the central 

 nervous system. 



4. Cybulski. — Method of stimulating muscle and nerve by 

 means of condensor discharges. 



5. Mares. — Nerve excitation by means of varying induced 

 currents due to variations in the rapidity of magneto-induc- 

 tion. 



6. Wedensky. — The most favourable and the least favourable 

 frequency for effective intermittent excitation of nerve by elec- 

 trical currents. 



7. Paton. — A crystalline globulin obtained from urine. 



In addition the following members showed instruments and 

 models : — 



1. Lahousse. — Model of the nerve centres. 



2. Rosenthal. — Calorimeter with recent improvements. 



3. Laulanie. — (a) A universal inscribing manometer. 



{b) .Apparatus for studying respiratory 

 changes. 



4. Morat. — Recording apparatus. 



5. Cybulski. — The Photohsemotachometer. 



6. Miescher and Jacquet.— A recording chronometer. 



On Wednesday evening, at the conclusion of the proceedings, 

 the members dined together in the large foyer of the theatre, 

 the President of the Congress, Prof. Holmgren, being in the 

 chair. 



NO. I 194, VOL. 46] 



As the Congress is held every three years, the next meeting 

 will take place in 1895, and it was decided that in response to 

 the kind and cordial invitation of Prof. Kronecker, the meet- 

 ing should be held in Berne (Switzerland). 



ELECTRO-METALL URG F.i 



'T'HIS is not the first time a lecture has been delivered here on 

 -*■ electro-metallurgy, I find that so long ago as January, 

 1841, there was a lecture on the subject by Mr. Brand. 



At that time electro-metallurgy was very new and very smill. 

 It consisted solely of electro-plating and electrotype. Electro- 

 plating had already begun to be practised as a regular industry, 

 but it was still a question whether the new kind of plating was 

 good, and there were not a few silversmiths who would not offer 

 electro-plate for sale because of its supposed inferiority to plate 

 of the old style. That question has long been definitely settled 

 by the fact that every week more than a ton of silver is deposited 

 in the form of electro- plate. 



Electrotype in 1841 was not so far advanced— it had not then 

 been taken hold of by the artisan and manufacturer — it was still 

 in the hands of the amateur. 



While the voltaic battery was the cheapest source of electric 

 current, electro-metallurgy was necessarily restricted to artistic 

 metal work, or to those applications where the fine quality of 

 the electrotype cast outweighed the consideration of its cost, or 

 where only a thin film of metal was required for the protection 

 of a baser melal from the action of the air. 



Within this limited field, the electro deposition of copper, of 

 gold, of silver, of iron, and of nickel, has been carried on com- 

 mercially with very great success and advantage for almost the 

 whole period of the existence of the art. But beyond these 

 bounds, set by the limitation of cost, it could not pass. 



Now, all this is changed— since engineer and electrician have 

 united their efforts to push to the utmost the practical effect of 

 Faraday's great discovery, of the principle of generating electric 

 currents by motive power. The outcome is the modern dynamo, 

 with its result— cheap electricity. The same cause that has led 

 to eleclric lighting, and to the electric transmission of power, 

 has also led to a very great development of electro-metallurgic 

 industry, and not only in the old directions but in new. It is no 

 longer a matter of depositing ounces or pounds of metal, but of 

 tons and thousands of tons. And it is no longer with metal 

 deposition merely that electro-metallurgy now deals, but also 

 with the extraction of metals from their ores, and the fusion and 

 welding of metals. Electro-metallurgy has in fact grown so 

 large and many-branching, that it is impossible to treat it in a 

 complete manner in a single hour. 



One of the latest developments is electric welding. This, in 

 one of its forms, that invented by Elihu Thompson, has recently 

 been so thoroughly explained and demonstrated by Sir Frederick 

 Bramwell, that it is not necessary for me to do. more than 

 mention it as belonging to the subject. 



There is also another species of electric welding — that of Dr. 

 Benardos — in which the eleclric arc is used after the manner of 

 a blowrpipe flame, to obtain the welding of such forms and 

 thicknesses of iron, steel, and other metals, as would be difficult 

 or impossible to weld in any other way ; and not only is the 

 electric blow-pipe used for welding, but also for the repair of 

 defects in steel and iron castings, by the fusion of pieces of metal, 

 of the same kind as the casting, into the faulty place, so as to 

 make it completely sound. This new kind of electric welding, 

 as improved by Mr. Howard, is now of sufficient importance to 

 entitle it to the full occupation of an evening. I therefore 

 propose to leave it for detailed description to some other lecturer, 

 and content myself with calling your attention to the interesting 

 collection of specimens on the table, and in the Library (lent by 

 Messrs. Lloyd and Lloyd), showing the results of this process. 



Even with this curtailment, the extent of the field is still too 

 great, and I must reduce it further by omitting a considerable 

 section of that portion which relates to the extraction of metals 

 from their ores, and, in this connection, only speak of the 

 extraction of aluminium. 



But, in the first place, I am going to speak of the deposition 

 of copper, and you will pardon me if I treat it as if you were 

 unacquainted with the subject. 



2d by Mr. J. Wilson Swan, at the 



1 Friday evening discourse delive 

 Royal Institution, on May 20. 



