May io, 1894] 



NA TURE 



39 



that the hardness conferred upon tool steel when plunged at a 

 good red heat into cold water was due, not to carbon, but to the 

 presence of 8 iron, rendered stable at low temperatures on being 

 suddenly chilled in the presence of carbon, the last-named ele- 

 ment, as such, possessing a comparatively insignificant harden- 

 ing influence. M. Osmond also said that an investigation made 

 on a series of alloys had verified Prof Roberts-Austen's law that 

 the influence of elements on iron is in accordance with the 

 periodic law. These, briefly, are the points on which Prof 

 Arnold joined issue ; and in order to support his contention, 

 he has made a vast number of experiments which he claims, if 

 we understood him correctly, entirely upset the theories of M. 

 Osmond and Prof. Roberts-Austen. 



The paper by Mr. Iladfield, to which we have referred, is 

 entitled "The Results of Meat Treatment on Manganese .Steel 

 and their Bearing upon Carbon Steel." Mr. Hadfield's 

 connection with that remarkable alloy of iron known as 

 manganese steel is well known, and the great difliculty with 

 which it is magnetised renders it especially interesting in 

 connection with this subject. During the discussion Mr. 

 Hadfield showed that manganese steel may be m.ade magnetic ; 

 in fact he produced a bar which was distinctly at^'ected by the 

 magnet at one end, whilst at the other end there were no 

 magnetic properties. We must, however, refer our readers to 

 the Transactions for the many interesting details contained in 

 this paper. The meeting terminated with the usual votes of 

 thanks. 



The summer meeting this year will be held in Belgium, 

 commencing on Monday, the 20th August, when members will 

 assemble in Brussels. The meeting will extend until the 

 following Friday, so as to give members an opportunity to 

 travel home on the Saturday. 



THE ROYAL SOCIETY'S CONVERSAZIONE. 



'T'HE first (or gentlemen's) soiree of the Royal Society took 

 place on the evening of May 2, in the Society's rooms at 

 Burlington House. There were numerous exhibits, and it will 

 be seen from the following summary that most branches of 

 science contributed evidences of progress. 



Prof Hunter Stewart and Mr. Henry Cunynghame exhibited 

 apparatus for micro-photography. 



Experiments in persistence of vision were shown by Mr. Eric 

 S. Bruce. 



Mr. J. Theodore Bent exhibited antiquities and anthropo- 

 logical objects from the Hadramoot, Southern Arabia. 



Two models of the South Lodge Camp, Rushmore Park, 

 Wiltshire, an entrenchment of the Bronze age, before and after 

 excavation, with the relics therefrom, were shown by General 

 Pitt-Rivers ; and also two models of the Handley Hill entrench- 

 ment before and after excavation, on the same scale as the South 

 Lodge Camp, with the relics therefrom. 



New Dicynodont reptiles from South Africa were exhibited by 

 Prof IL G. Seeley ; and a skull of Deuterosaurus. 



Mr. Richard Kerr showed an ovate palaeolithic implement 

 and two molar teeth of Rhinoceros lichorhiniis, found by him 

 in brick-earth at St. John'sroad, Radnor Park, Folkestone, in 

 August 1S93. 



Chemistry was represented by Dr. J. H. Gladstone's exhibit 

 of early specimens of partly soluble cotton xyloidin, and of 

 Austrian gun-cotton for military purposes. In 1S47 the ex- 

 hibitor prepared xyloidin from starch and from cotton. His 

 specimens have all spontaneously decomposed, except those 

 shown, which are mixtures of the soluble cotton xyloidin 

 and ordinary gun-cotton. 



Some maps and plans which accompany the Report on 

 Nile Reservoirs, recently published by the Egyptian Government, 

 were exhibited by Prof J. Norman Lockyer. 



Mr. J. Wimshurst exhibited models showing an improved 

 method of communication between shore stations and light-ships, 

 or other like purposes. 



Mr. k. E. Crompton showed an electrically healed altar 

 and electiically heated soldering bits for soldering and brazing ; 

 and a potentiometer, to measure electromotive forces, from 

 ■0001 to 1500 volts, correctly to 1 2000 ; and Sir David 

 Salomons showed some new phenomena in " vacuum lubes." 



Mr. Owen Glynne Jones ^exhibited his absolute and relative 

 viscosimeters. 



NO. 1280, VOL. 50] 



Prof. Roberts-Austen's exhibit comprised an ink-recording 

 pyrometer, consisting of a thermo-junction of platinum and 

 platinum iridium attached to a dead b^at galvanometer, and a 

 series of pyrometric curves obtained by photographic recorders in 

 different iron works, and showing the temperature of the hot 

 blast used in smelting iron. 



Mr. A. E. Tutton exhibited an instrument of precision for 

 producing monochromatic light of any desired wave-length, and 

 an instrument for grinding section-plates and prisms of crystals 

 of artificial preparations accurately in the desired directions, 

 (lioth these instruments are described in Nature, vol. xlit. 



Dr. Karl Grossmann and Mr. J. Lomas exhibited crystals of 

 ice (hexagonal hopper) and photographs. 



Dr. Karl Grossmann showed some specimens of Obsidian 

 from Iceland. The specimens were brought by the exhibitor 

 from the Hrafntinnuhryggur in Iceland (N. E.) The large 

 specimen showed conchoiJal fracture, evidently produced on 

 falling from a cliff. Ttie smaller specimen shows floia 

 structure. 



A twin-elliptic pendulum and pendulum figures were ex- 

 hibited by Mr. Joseph Goold ; and a glass model, showing a 

 method of transmitting force by spheres or discs, by Mr. 

 Killingworth Hedges. 



.\n exhibit which attracted much attention was M. Moissan's 

 electric furnace, and specimens of chemical elements obtained 

 by means of it : vanadium, chromium, molybdenum, tungsten, 

 uranium. The furnace consists of a parallelepiped of limestone, 

 havmg a cavity of similar shape cut in it. "This civity holds a 

 small crucible, composed of a mixture of carbon and magnesia. 

 The electrodes are made of hard carbon, and pass through holes 

 cut on either side of the furnace, meeting within the cavity. 

 For the purpose of certain experiments a carbon tube was fixed 

 in the furnace at right angles to the electrodes, and so arranged 

 as to be 10 mm. below the arc, and about the .•^ame distance 

 from the bottom of the cavity. This tube contains the material 

 to be heated, and by inclining it at an angle of about 30' the 

 furnace may be made to work continuously, the material being 

 introduced at one end of the tube and drawn off at the other. A 

 temperature of about 3500' C. is produced. The metals are re- 

 duced by heating a mixture of their oxides with finely divided 

 carbon, and for this purpose a current of about 600 amperes and 

 60 volts is employed. M. Moissan has not only succeeded in 

 reducing the most refractory metali, but has fused and volatilised 

 both lime and magnesia. Nearly all the metals, including iron, 

 manganese, and copper, have also been vapourised, whilst by 

 fusing iron with an excess of carbon, and then quickly cooling 

 the vessel containing the solution of carbon in molten iron by 

 suddenly plunging it into cold water, or better into a bath of 

 molten lead, he has been successful in producing small colour- 

 less crystals of carbon, identical in their properties with natural 

 diamonds. 



A new harmonic analyser was exhibited by Prof. Henrici. 

 This analyser differs from that shown last year by an im- 

 proved integrating apparatus. The maker, Herr G. Coradi, of 

 Ziirich, has introduced a glass-sphere, whereby all slipping has 

 been avoided, and greater compactness has been obtained. 

 The instrument exhibited gives only one term (two coefficients) 

 in Fourier's expansion at a time, but on going six times over 

 the curve to be analysed as many terms can be obtained. 

 There is no difficulty in introducing more integrators in the 

 same instrument, and one has been made which gives five terms 

 on going once over the curve, and ten in going twice over it. 



Callendar and Griffiths' long distance direct-reading electrical 

 thermometers and pyrometers were shown by Mr. E. II. 

 Griffiths ; and a torsional ergometer or work-measuiing machine, 

 used in connection with a mechanical integrator and as an 

 electrical governor, by the Rev. F. J. Smith. 



Mr. Henry Wilde showed his magnelarium for reproducing 

 the phenomena of terrestrial magnetism and the secular changes 

 in its horizontal and vertical components, and a magnetometer 

 for showing the influence of temperature on the magnetisation 

 of iron and other mignetic substances. 



Polyphase electric currents were illustrated by Prof. Silvanus 

 P. Thompson, with models and experiments. 



The Marine Biological Association contributed living pelagic 

 larvii;, tVc, from I'lymouth, examples of the echinoderm fauna 

 of Plymouth, and a hybrid between brill and turbot. 



Mr. Henry A. Fleuss showed a mechanical pump for the 

 rapid production of very high vacua, and vacuum tubes ex- 



