540 



NATURE 



[OCTUBEK 13, 1923 



identical with the (lis|K)siti<.ii of ntoms suggested by Sir 

 VVilhaiii HraKW for thoinotr. nhi.l I .. n/fne " (Challenor 



and Infold, I ! ' ■ id 



scarcely tie ni,» 'M 



of a possible -..\ < iiiiKa^^c m nipi';! 1 icrna- 



tives iiitroduci entially novel 1 <in 1 deration 



to tlu^ <|nestioii (m wf tiiutiire of these 1 < impounds. 

 I .ill 1 rctc! red in ni\ lei t'l tot he rciii.itiwdilf Ix-liaviour 

 ol diplienyl Unvards u/.oiic, iiiuntioind l>\ I ir Inrner, 

 ;is well as to certain other notewi t li\ jiiii|h itw . .,1 

 the ( oinpound. 



li sIk mid perhaps be pointed out tli;it aiilioi' 

 I)r, I inner states, the formula lonsideied 1>., 

 coiiluius \i K ' III I ,irl)on atoms, it would Ik- 



inioneet I' , ; ' ' lli.il It tiieretore demands tiie 



existence of a coi icspondin^h- lar^e nnmlier of 

 stcreoisonieric forms ol j : j' deri\ati\t'^ ol diiiiienvl. 

 I '"or t he resju'ctixc disl nlmt ions ol' tlu- L;rou]>~. ;in ;i( In-d 

 to the j)air of as\inmetne (arlion alom.s 111 either 

 benzene nucleus are not mutmilK independent, so 

 that only one asymmetric atom m each nucleus is 

 effective as a source of stereoisomerism. 



In conclusion, I need scarcely say that experiments 

 on the isomerism in question arc lieinj; ac ti\elv 

 prosecuted in this laboratory, and are by 110 mi-.ins 

 limited to 2 : 2 '-derivatives of diphenyl. 



J. K I \Mj;. 



The Chemical Department, The University, 

 Sheffield, September 25. 



Waves and Quanta. 



The quantum relation, energy =/; x frequency, leads 

 one to associate a periodical phenomenon with any 

 isolated portion of matter or energy. An observer 

 bound to the portion of matter will associate with 

 it a frequency determined by its internal energy, 

 namely, by its " mass at rest." An observer for 

 whom a portion of matter is in steady motion with 

 velocity fie, will see this frequency lower in con- 

 sequence of the Lorentz-Einstein time transformation. 

 I have been able to show {Cotnptes rendus, September 

 10 and 24, of the Paris Academy of Sciences) that 

 the fixed observer will constantly see the internal 

 periodical phenomenon in phase with a wave the 



frequency of which v - — pJ=r^ is determined by the 



quantum relation using the whole energy of the 

 moving body — provided it is assumed that the wave 

 spreads with the velocity c/jS. This wave, the velocity 

 of which is greater than c, cannot carry energy. 



A radiation of frequency v has to be considered 

 as divided into atoms of light of very small internal 

 mass (<- lo'^" gm.) which mo\ e with a velocity very 



nearly equal to c given by ' .,hv. The atom 



\ ' "' '' 

 of light slides slowly upon the non-material wave 

 the frequency of which is v and velocity c/,S, very 

 little higher than c. 



The " phase wave " has a very great importance 

 in determining the motion of any moving body, and 

 I have been able to show that the stability conditions 

 of the trajectories in Bohr's atom express that the 

 wave is tuned with the length of the closed path. 



The path of a luminous atom is no longer straight 

 when this atom crosses a narrow opening ; that is, 

 diffraction. It is then necessary to give up the inertia 

 principle, and we must suppose that any moving body 

 follows always the ray of its " phase wave " ; its 

 path will then bend by passing through a sufficiently 

 small aperture. Dynamics must undergo the same 

 evolution that optics has undergone when undula- 

 tions took the place of purely geometrical optics. 

 Hypotheses based upon those of the wave theory 

 allowed us to explain interferences and diffraction 



NO. 2815, VOL. 112] 



fringe. By means of these new i<leas, it will probably,^ 

 be possihln to reconcile also diffusion and di-spersioti ' 

 witfi ■ ontinuity of light, an<l to solve almost 



all 1 us brought up by quanta. 



Louis :' : ;• 



September 12, 



The *« Concilium Bibliof^raptm um. 



1- t !;< ( ommentary add( letter c<ji 



!i' < ' • 1 :hinn P.ihlir)(^ra; which aj 



' '. 6iio, some doubUs «<:■ 



ontinuous appcaranrf - f 

 1! . i.iiil iitte<l to empnasi-' 



thai our nd delivererl as h< ; 



to Oli 1 



Ai- .bill :it ion 0! t !.' :iiin is \:-i- 



" I'lbih ..';.:; Jii.i /oolo > ■.nun volumes 30 and 



^i li:i\e been [lubii'li- I, 32 will l>esent out 



sliorih , iiulu .itniL^ deliiiiLii_\ iii.it this zoological bibho- 

 grapli\ i- not a new undertaking of the Concilium. 



No tloubt it is a rather complicated '■■■-.•"■- to 

 decide whether or not tins zoological bil ni 



l)f)ok form is .i dnjilK ation of the " Zoologii.... ..^ .■,;.i." 



It must bi' r((,dl( 1 that apart from completeness, 



proini>in( --., ;,^i , sil.ihtv. carefulness and the 



proccduie in of the bibliographical 



work play a role. Indeed, as for 



every application edure, it 



only the tools but of abilit- 



them wdiich go\-ernr. liii- ajipi. ._ i.iiion (-■ :..,, 



have to work with them. IJne works ;!li 



one method, another is more adapted to the use of 

 another. To all these points have to be added as 

 important factors the influence of di; lucation 



and local tradition. 



In making a plea for a co-operation between the 

 " Zoological Record " and the bibliographical service 

 of the Concilium, a condition which unquestionably 

 could be of real value to the zoological world, the 

 writer wishes to suggest that these various important 

 p>oints of internal character be seriously considered. 



When it was decided in 192 1 to continue the book- 

 form of the " Bibliograiihia Zooloidca," the material 

 to be published was so cxtdisive that it was impossible 

 to treat the whole animal kingdom in ever}' volume. 

 But this is certainl}- not a misfortune, for it is evident 

 that a bibliography of titles has not only an immediate 

 value, but also represents to a great extent a source 

 for continuous reference. J. Stkohi., 



Director of the " Concilium 



Zurich. Bibliographicum." 



Long-range Particles from Radium-active Deposit. 



In the letter which appeared in ^ of Sep- 



tember 15, p. 394, under this headr Kirsch 



and myself, there are two errors v\ ;...,. v.,.-^ure the 

 sense of our communication. The maximum range 

 of the H-particles expelled from silicon should read 

 12 cm., the corresponding number for beryllium being 

 18 cm., instead of vice versa. The last sentence 

 should read : " Our results seem to indicate that an 

 expellahlc H-nucleus is a more common constituent of 

 the lighter atoms than one has hitherto been inclined 

 to believe," the word in italics being omitted in the 

 printing. H.ws Pettersson. 



Goteborgs Hogskola, Sweden. 



[The transposition of tlie \alues 12 cm. and 18 cm. 

 was tlie fault of our printers ; and we much regret it. 

 The omission of the word " expellable " was due to 

 the authors, who did not include the word in their 

 letter. Two separate proofs of the letter were sent to 

 Dr. Kirsch at \'ienna, but neither was returned. — 

 Editor, Xatikf..] 



