June 7, 1894] 



NA TURE 



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'OJ 



exhibition, to be held in connection with the meeting, should 

 >'rite to the " Ausstellungs Comiteder Naturforscher-versamm- 

 'lung, Wien., Universitat." 



Proposed Astronomical Congress in 1896.— At the end 

 nf a paper read at the last meeting of the Royal Astronomical 

 society. Dr. Gill propounded the following questions, which 

 we reprint from the Observatory, (i) Whether, in the opinion of 

 astronomers generally, steps should be taken I'or a more com- 

 plete and harmonious organisation and partition of the astro- 

 nomical world from the year 1900? (2) Are astronomers pre- 

 pared to enter upon a preliminary study, discussion, and experi- 

 ment on I he practical methods by which the art of observation 

 may be raised to a higher level of accuracy, and its results be 

 <lerived and published in a more systematic and homogeneous 

 system? (3) If these questions are answered in the affirmative, 

 would it be desirable to hold an international astronomical 

 congress, say in 1S96, to discuss and make ihe necessary pre- 

 liminary arrangements, and then let the definitive programme 

 and partition of work be made at another general congress to 

 be held in the year 1899? 



The Law and Greenwich Time. —Is there any legal 

 authority for the use of Greenwich Time throughout Great 

 Uritain? The editors of ihe Observatory point out that in 

 the Statutes (Definiiion of Time) Act 18S0, 43 and 44 Vic. 

 cap. 9, it is enacted that whenever any expression of time 1 

 occurs in any Act of Parliament, deed, or any other legal j 

 instrument, the time referred to shall, unless it is otherwise 

 specifically slated, be held in the case of Great Britain to be 

 Greenwich Time, and in the c.ise of Ireland, Dublin Time. It 

 is remarked, however, that Sir James Stephen says, in the 

 Larceny .-Kct, "Ciiminal Law Digest," p. 247, sec. 3, in re- 

 ferring to the exptessi n " of the clock " ; — " It may be worth 

 while to observe that the expression ' nine of the clock,' 'six 

 of the clock,' indicates mean as opposed to solar lime ; but a 

 question might arise as to whether they mean local mean 

 time or the mean time commonly observed at any given 

 place. London time, or, as it is called, railway time, is now 

 very generally observed, and there is a difference of more than 

 twenty minutes between London and Cornwall. Local mean 

 time is the natural meaning." In the case which led our 

 contemporary to look up the matter, a defendant arrived at 

 a court at the local (Carlisle) time appointed by the court to 

 sit, but found that the court had met by Greenwich Time, and 

 had decided against him. The difference of interpretation of 

 Ihe time appointed led to the granting of a new trial. 



THE WORK OF HERTZ> 



"TTHE untimely end of a young and brilliant career cannot fail 

 ■'■ to strike a note of sadness and awaken a chord of sympaihy 

 in the hearts of his friends and fellow-workers. Of men thus 

 cut down in the early prime of their powers there will occur to 

 us here the names of Fresnel, of Carnot, of Clifford, and now 

 of Hertz. His was a strenuous and favoured youth ; he was 

 surrounded from his birth with all tlic influences that go to 

 make an accompli-hed man of science — accomplished both on 

 the experimental and on the mathematical side. The front rank 

 of scientific workers is weak r by his death, which occurred on 

 January i of the present year, the thirty-sixth of his life. Yet 

 did he not go till he had effected an achievement which will 

 hand his name down to posterity as the founder of an ei>och in 

 experimental physics. 



In mathematical and speculative physics others had sown the 

 seed. It was sown by Faraday, it was iown by Thomson and 

 by Stokes, by Weber also doubtless, and by Ilelmholtz, but in 

 this particular department it was sowed by none more fruitfully 

 and plentifully than by Clerk Maxwell. Of the seed thus sown 

 Hertz reaped the fruiis. Through his experimental discovery, 

 Germany awoke to the truth of Clerk Maxwell's theory of light, 

 of light and electricity combined, and the able army of workers 

 in that country (not forgetting some in Switzerland and France 

 and Ireland) have done most of the gleaning after Hertz. 



This is the work of Hertz which is best known ; the work 

 which brought him immediate fame. It is not always that 

 public notice is so well justified. Ttie popular instinct is 

 generous and trustful, and it is apt to be misled. The 

 scientific eminence accorded to a lew energetic persons by 



' A Lecture delivered .-»t ihc Royal Institution on Friday, June i, by 

 Prof. Oliver Lodge F. R.S . ably ass.>ted during both prep.lration anl 

 performance by Mr. Edward K. Robinson. 



NO. 1 :84. VOL. 50I 



the popular estimate is more or less amusing to those work- 

 ing in the same lines. In the case of Heriz no such mistake has 

 been made. His name is not over well known, and his work 

 is immensely greater in every way than that of several who 

 have made more noise. 



His best known discovery is by no means his only one. 

 I have here a list of eighteen papers' contiibuted to 

 German periodicals by him, in addition to the papers in- 

 corporated in his now well-known book on electric waves. I 

 would like to suggest that it would be an act of tribute, useful 

 to students in this country, if the Physical Society of London 

 saw their way to translate and publish a collection of, at 

 any rate, some of these papers. 



Por.'rait Slide. 



The portrait which I show is not a specially pleasing one. It is 

 from a photograph taken by Mr. Vule, one of the band of foreign 

 students who flocked to Hertz's laboratory at Bonn. It is ex- 

 cellent as a photograph, though it fails to represent Hertz at 

 his best ; perhaps because it was not taken till after the 

 pharyngeal trouble had set in, which ultimately carried him off. 



In closing these introductory and personal remarks, I should 

 like 10 say that the enthusiastic admiration for Hertz's spirit and 

 character, felt and expressed by students and workers who 

 came into contact with him, is not easily to be exaggerated. 

 Never was a man more painfully anxious to avoid wounding the 

 susceptibilities of others ; and he was accustomed to deprecate 

 the prominence given to him by speakers and writers in this 

 couniry, lest it might seem to exalt him unduly above other 

 and elder workers among his own sensitive countrymen. 



Speaking of the other great workers in physics in Germany, 

 it is not out of place to record the sorrow with which we 

 have heard of the recent death of Dr. August Kundt, Pro- 

 fessor in the University of Berlin, successor of von Helm- 

 holtz in that capacity. 



When I consented to discourse on the work of Hertz, my 

 intention was to repeat some of his actual experiments, and 

 especially to demonstrate his less known discoveries and obser- 

 vations. But ihe fascination exerted upon me by electric oscil- 

 lation experiments, when I, too, was independently working 

 at them in the spring of 1S88.- resumed its hold ; and my lecture 

 will accordingly consist of experimental demonstrations of the 

 outcome of Hertz's work rather than any precise repetition of 

 portions of that work itself. 



[n case a minority of my audience are in the predicament of 

 not knowing anything about the subject, a five minutes' ex- 

 planatory prelude may be permitted, though time at present is 

 very far from being " infinitely long." 



1 Hertz's Papers. 



iS73-79. \yi€d..Ann.^ i8So. vol. lo. p. 414. Experiments to establish an 

 Upper Limit lor the Kinetic Energy of Electric Flow. 



iiJSo. Inaugural Dissertation (Doctor Thesis) oti Induction in Rotating 

 Spheres. 



iS8t. Vol. 13, Wicd. Ann., p. 266. On the Distribution of Electricity on 

 the Surface of Moving Conductors. 



1883. March. Schtotnitclt Zeitschrift^ p. 125. On the Distribution of 

 Pressures in an Elastic Circular Cylinder. 



i83i(?) Crelle. vol. 92. p. is6. Un the Contact of Solid Elastic Bodies. 



1882. Verlinndlnngei des I'ercins des t,V:i'er^//^/r.s«(Sonderabdriick). On 

 the Contact of Solid Elastic Bodies and on Hardness 



i83i. Vol. T4, l^ied. Ann., p. 581- Upper Limits forthe Kinetic Energy 

 of Moving Electricity. 



1882. IVied. Ann., vol. 17, p. 177. On the Evaporation of Liquids, 

 especially of Quicksilver, in Air- Free Space, and on the Pressure of 

 Mercury Vapour. 



1883. IVied. Ann., vol. 23, d. 275. On the Property of Benzine as an 

 Insulator and as showing Elastic Reaction (Ructcstandsbildner). 



i832. I'erltandln. d. phys. Gesetlsdtaft in Berlin, p. 18. On a New 

 Hygrometer. 



1883. IVied. Ann., vol. 19, p. 78. On an Appearance accompanying 

 Electric Discharge. 



1885. /i., vol. 19, p- 7S2. Experiments on Glow Discharge. 



1883. Zeitschrift fiir Instrnmentenkunde. l>ynamometric Contrivance 

 of Small Kesis'ance and Intinitesimal S=lf- Induction. 



18B4. -I/c/. Zeitschrift, November, December. Graphic Methods for the 

 Determination of the Hdiabatic Changes of Condition of Moist Air. 



1884. Wied. Ann., vol. 22, p. 449. On the Equilibrium of Floating 

 Elastic Plates. 



i83l. It^-, vol. 23. On the Connection between Maxwell's IClectrodynamic 

 Fundamental Equations and those of opposition Electrodynamics.^ 



1885. //'., vol. 24, p- 114. On the Dimension of a Magnetic Pole in 

 difTerent Systems of Units. 



1887-1889. Papers incorpora'eil in his book, " .^usbreitung der'Elek- 

 trischen Kraft," translated under the tide of ■' Electric Waves." 



1892. iVicd .Ann., vol. 45. p. a8. Un the Pas.sage of Cathode Rayi 

 through thin Metal Sheets. 



•-' Pliil. .'ilag , xxvi. pp. 329, J20. Auguit 1888 : or " Lightning Con- 

 ductors and Lightning Guards " tWhittaker), pp. 104, 105 ; also Frvc. Rffy. 

 Sm. vol. I. p. a;. 



