138 



NA TURE 



[December 8, 1898 



8pec(ruin wn.s described by Ilugg'ins to the Koyal Society in 



'879- 



In 1881, lluci;ins siiccecdc<l in photogmphing llie sped rum 

 of Tebbult's cornel, and, availing hiinscif of the v.irii)us improved 

 appliances which were suRgesteil f)y his unicpie experience, he 

 photographed the speclrum of the Orion neliulae in 1882. In 



1888, a slill better photograph of the same spectrum was 

 obtained by Dr. and Mrs. Iluggins. There was a special 

 interest about this plate. It showed that certain bright lines 

 were common to the nebula and to the trapezium stars, thus 

 establishing the connection between the stars and the nebulae. 

 Further investigations of the same object were also made in 



1889. In that same year the speclrum of Uranus was investi- 

 gated photographically by Dr. and Mrs. Muggins, and was 

 shown to be essenti.tlly solar. In i.Sgo, the chief line in the 

 nebular spectrum was accurately re-delermined, and an invesli- 

 gati(m was made by Dr. and Mrs. Muggins of the spectra of 

 Wolf and Rayet's stars in Cygnus. 



The most recent work from the Tulse Mill Observatory has 

 been the investigation of ihe remarkable ultraviolet lines of 

 calcium, by which the characteristics of these lines in the solar 

 spectrum have been explained. 



.\ sketch of the early history of spectroscopic astronomy was 

 given by Dr. Muggins to the Hritish Association, at Nottingham, 

 in 1866. A review of the same subject a quarter o( a century 

 later is found in his Presidential -Vddress at the Cardiff Meeting 

 of the As.sociation in 1891. Reference must al.so be made to a 

 lecture on the remarkable star. Nova Aurigae, given at the 

 Koyal Institution in 1S93. 



A full list of Muggins's papers, up to the year 1894, i^ found 

 in Krost's translation of Scheiner's "Astronomical Spectro- 

 scopy," published by dinn and Co., 1894 



The Rumford Medal is given to I'rof. Oliver J. Lodge in 

 recognition of his researches on radiation and on the relations 

 Oetwcen matter and elher. 



In dealing with the history of the discovery by Prof. Ilerti of 

 olcctro-magnelic radiation, it would be impossible to pass over 

 the work done previously, or simultaneously, by Prof. I.ixlge, on 

 the surging or oscillatory character of the transmission of electric 

 <lischarges along wires. 



Prof Lodge gave an account of his observations in his lectures 

 to the Society of Arts, delivered in 1 888, which are incorporated 

 in his lreali.se on " Lightning Conductors and Lightning 

 <iuards," published in 1892. 



The researches of the Knglish ami tjerman physicists were 

 entirely independent, and though the merit of the actual dis- 

 covery of eleetro-magnelic radiation belongs certainly to Prof. 

 Ilerlr, there seems lillle reason to doubt that Prof. Lodge's 

 experiments would have led him eventually to the same result. 

 Prof. Ilett?. himself says, in the introduction to his work, 

 " Ueber die Ausbreilung der Klektti.schen Kraft " : " Inasmuch 

 ns he" (Prof, Lodge) " entirely accepted Maxwell's views, and 

 eagerly strove to verify them, there can .scarcely be any doubt 

 that, if I had not anticipated him, he would also have succeeded 

 in observing waves in air, and thus also in proving the pro[)aga- 

 lion with time of electric force" (p. 3, Knglish edition). 



When the discovery of electromagnetic radiation was an- 

 nounced. Prof. Lodge at once recognised it.s great im|)ortance, 

 and by his lectures and writings contributed largely to make 

 known to this country the brilliant achievement of llertr. Al 

 the same lime, by his experimental investigations, be added 

 considerably lo the knowledge of the subject, and maletially 

 .strengthened ihe evidence thai electro-magnetic waves exhibit 

 similar properties lo those which have been for a hmg lime 

 assigned 10 the ethereal disturbances assumed lo constitute 

 the mechanism by which are produced the phenomena of light. 

 Prof. Lodge's introihulion of the "coherer"— an instrument 

 the action of which is based on oKservalions made indepenilently 

 \yj himself and M. llranly- as a substiiute for the Merit 

 " resonator," has increased in a marked degree ihe facility for 

 reproducing and extending the experiments of Prof. Mert/, and 

 has furnished ihe means of exhibiting much more conspicuously 

 he results obtained. 



More recently Prof. Lodge has b^-en engaged in investigating 

 the phenomena presented by ihe Ronlgen lays, and ihe circum- 

 stances under which these rays are produced. Me has also 

 studied Ihe efTect on the light emilled from a source placed in a 

 powerhd magnetic field, which was discoveretl by Prof, 

 /eeman. 



In connection with all these branches of inquiry, he has com- 



NO. I 5 19, VOL. 59] 



niunicated to scientific societies and to periodicals a large 

 number of papers, containing valuable contributions to our 

 knowledge of radialions in ether, and suggestive speculations as 

 to the properties of the ether itself. 



With the object of obtaining some information as to the pro- 

 perties of the ether, and of ascertaining whether any mech inical 

 connection can be delected between matter and ether. Prof. 

 Lodge carried out an elaborate series of experiments, of which 

 the record ap|x;ars in the PhUosophiial Traiisiulions, voli, 

 184 and 189. The special aim of this research was to 

 <letermine whether a moving mass communicates any corrC' 

 sponding motion to the ether in its immediate neighlxiurhood, 

 or, in other words, to determine whether the einer has any 

 apparent adhesion to matter, and possesses any property of the 

 naUire of, or analogous to, viscosiiy. 



Mis method of observation is to divide a beam of light into 

 two of equal intensity, and to cause Ihe latter to traverse in 

 opposite directions an annular space in a steel or inm disc. The 

 two beams are superposed so as to produce interference-bands. 

 If any appreciable motion can be communicated to Ihe ether in 

 the annulus by causing the disc to revolve rapidly round the 

 common axis of the disc and Minulus, it is practically certain 

 that some change must be produced in the velocity of the light 

 in the two beams, and this change must show itself by an 

 observable displacement of the interference-bands. 



No such displacement was observed with any velocity of the 

 disc which could be attained, nor could any shift of Ihe bands be 

 detected when the annulus in the revolving disc w.os converted 

 into a powerful m-tgnelic field, or was subjected to strong 

 electrification. 



The absence of any noticeable effect upon the light in these 

 experiments is taken to indicate that matter has no appreciable 

 hold upon the ether in its neighbourhood, and that no power of 

 gripping the elher is conferred upon matter cither by magnet- 

 isation or electrification of the kind empUiyed. 



[As it is a condition that a \i\x\. at least of the work on which 

 a claim to the Rundord Medal can be founded should have been 

 published during the two years preceding Ihe award, a list is 

 appended containing the titles of some of Prof. Lodge's pipers 

 which have appeared during 1896-98 : — 



(1) " Lxperimenison the Absence of Mechanical Connection 

 between Ether and Matter" (PhU. Trans., A, 1897, voL 

 :S9). 



(2) "The Influence of a Magnetic Field on Radiation 

 Frequency" (Koy. Soi. Prot., vol. 60). 



(3) " Further Note on the Influence of a Magnetic Field of 

 Radiation Frequency" (Koy. Soi\ Prtu., vol. 61). ^ 



(4) " Note on .Mr. Sutherland's Objection to the Conclusive- 

 ness of the Michelson-Morley Aether Experiment " (Phil. Mag,, 

 vol 46). 



(5) "On the Rays of Lenard and Ronlgen" (EUdncioM, 

 vol. 46). 



(6) "On the Present Hypotheses concerning the Nature of 

 Riintgen Riys" (Eleilrician, vol. 36). , 



(7) " I'"urther Progress in Radiography " (E/filn'iiaH, vol. 36). 



(8) " Ronlgen Rays" (EUctruian, vol. 37). 



(9) "The Surviving Hypothesis concerning Ihe X-Rays" 

 (Ettctriiiaii, vol. 37). 



Several short noies on subjects connected with Radiation hafC 

 appeared in N.\rrKK during 1 896 98. ] 



One of the Royal Medals is bestowed upon the Rev. John 

 Kerr, as the author of extremely imporlant experimental re- 

 searches on the optical relations of electricity and magnetism. 



Dr. Kerr has ma^le a name, which will always be remembered 

 in the history of science, by his exjierinients on the optical 

 effects of electrical and mechanical stress, and on Ihe (xjlarisa- 

 •lion of light reflected from the surface of a magnetised body. 



His observations on electrical stress were recorded in a series 

 of papers [Miblished in the /'.*//. Afag- in 1875, 1879 and 188a, 

 in which he demonstrated the fact that the velocity of polarised 

 light in a bixly subjected to electrostatic influence is different 

 according as the plane of jHilarisation is p^irallel or perpendicular 

 to the lines of electric force. 



In these exiierimenls he was led to use mechanically strained 

 gloss as an auxiliary apparatus, and in October 1S8S, he pub- 

 li.shed, in the Phil, .l/l^^'., an imporlant paper on "The 

 Hirefcingent .Vciion of Strained Class." 



In 1S77, Dr. Kerr (/'^/V. Mag. [5], voL J, p. 321) showed 

 that if plane |x>larised light is reflected ftooi a magnetised 

 surface, the |x>larisaiion of the reflected ray is affected by the 



