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Heinrich Rubens

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Heinrich Rubens Heinrich Rubens. Von Wilhelm Westp£al, Berlin. Am 17. Juli _1922 hat Heinrlch Rubens naeh Assistenten am .Berliner Insti~ut ernannt. Zu ]angem, schwerem Leiden ,die Augen geschlossen. dieser Zeit war es, Ms die Entdeekung tier elek- Nit ibm ist nicht n ur ein Forscher wo~, Weltruf, trischen WelIen und ihrer Eigenschaf%en durch nicht nur einer tier erfo]greiehste,n akademisehen Heinrich Hertz in entscheidenc}er Weise einem Lehrer Deutsehlands .da,hingegangen, sondern grol]en Teil seiner kfinftigen Lebensarbeit <tie aueh ein Mensch yon eigenartigem Gepr~ge, dem Wege wiesen. I.n seinem ~er[ihmten Vc~rtrage auf eine grolhe Zahl glterm: un~d jiingerer Faeh- der Naturf,or.scherversammlung in tIeidel'berg be- genossen in Verehrung anhingem Dieser Ver- tonte Hertz die Notwendigkeit, die Briieke yon ehrung sell @ieses, seinem Andenken gewidme~e der Op~ik zur Elelctrizitittsle'hre nnn'mehr auch Heft A~sdruck geben ,dadurch, dal3 sein Leben yon cter optisehen Seite her zu sch]agem DaB und Forsehen dutch d iejenigen Faehgeno~ssen dar- Rubens dieses gelang, mad win es ibm gelang, gestellt wird, welche ih~m als Ass~sZenten am wird immer zu den klassisehen ETeignissen in~ tier Physikalischen Institut der Universit:,tt ]herlin am Gesehichte der Physik gez~ihlt werden. Auf diese lgngsten 'amtlich und Fershnlich nahegestanden Wei.se wurde er vera~n~l.agt, sleh eingeh.en& mi£ tier haben. Wir wol]en damit unserm vecehrten Erforschung des ultraroten Spektratgebietes zu Lehrer ein. beseheidenes Denkmal errleh~cen als ~besch~ftigen, in ,gem er im wahrsten Sinne des Ansgruek einer tiefgeffihlten Dankess.ehuld. Nir Wortes Bahnbrecher gewesen ist, und mit dem sei. es gestattet, hler ein kurzes Lebens- ned Cha- sein N~ame ffir alle Zeiten verb~n,den b]eihen rakterb.ild zu geben, w~hrend die Darstellung der Wir6. Im ffahre 1896 wurde er an die Teeh- versehie&enen Zweige seiner ~,issens~hMtliehen nische ttoehschule Oharlotten'burg berufen u~d Lebensarbeit den folge~dlen Anfsggzen iiberlsssen 1900 zum ordentlichen Professor ernannt. Seine bleiben sell. wisseasehaftHche Tgti~gl~eit iib~e er w~hrend der Heinrich Rubens is~ ,geboren zu Wiesbaden am Zeit sdner Char]ottenB~urger Professur im 30. 2ffgrz t865. Er entstammte einer hotl~n- wesent]iehen an der ben,aehbarten PhysikalisCh- d isehen Kaufmannsfa:milie; sei~e Ehern .waren Technisehen R.eiehs~nsta]t .au,s. A'us dieser Zeit aus Amsterdam n~sch Deutseh]an~& fi~oengesledelt daiiert 11. a. die Entde6kung der Rest strahIen- Naehdem die Fami]ie ihren W<~hns:itz naeh methode un~g die ~essungen der EinergievertMlung t~ran~kfurt a. ]~f] verlegt hatde, ~besuehte Rubens im ~Spektrum 'des sehwarzen Khrt~ers, welche bi:s Ostern 1884 da,s ,dortige R,ealgymn, a.si~m. Ent- Planels die sichere experLmentelle Grundla~e zur spree henri der anf .des Pr:a~ktise:he geriehteten ~in- Aufstellung seiner Strah]ungsformel l ieferte~ ua8 stellung ,seiner Umge'b.u,ng ffhr~e seine friih anf- damit das Zeitalter der Qua'nten@e0rie und der t,retende Neign.ng zur P~ys.ik dazu, c~ag er sieh mo dernen Atem~heorie ein]~uten baleen. d:em Studium der Elektroteehn'ik zuwandte, dem Ira Sabre 1906 erfolgte Rubens" Berufung zum er ein Semester zu Darmstadt, zwei Semester zu Ordinarius und Direktor des, Physikalis,ehen I,n'- Cha¢lottenburg widmete. Nun mehr abet war er stituts an der Universldtt Berli:n Ms ~Naehfolger sieh dariiber ktar geworden, dab Be~i,gung und yon Paul Drude. ttier hat ,er ~nieh~ nur sell>st innere Neigung ihn mieht in .die Teehni~k, sonder'n, mit unermfidHchem Fleil] ,d~e hahn welter ver- zur rein wissensehaftliehen physikalisehen For- fo]gt, die er seh~n bisher in seinen Arbelten so sehnng drgngten. ~E.s .war der ,gleiehe Prozei], den erfolgreich beschrlkten ha±re, sonderr~ er konnte a u~ch Helnrich Hertz dur'ehmaeh~e, und die ~be- nur~mehr aueh elne grol~e Zah] yon SehiEern zur kannten Worte, mit..denen dieser seinen Ent- Mitarbeit heranziehen. Es btei'be .den nachfelgen- sehluB, zur relnen Physlk iiberzugehen, seinem den Au~sgtzen iiberlassen, .diese Arbei~en im ei,n- Vater brieflieh mi~teilte, treffen in weitem Urn- zelnen zu wfirdlgea, ttier sei nur darauf hin- range aueh auf Rubens zu. So bezog er im gewlesen, win ibm die Bezwlngu~g des ultraroten Winter.semester 1885 die Lrni~ersitRt Berlin, ver- SpektraIgeb[ets in ]'miner wei~erem ~zusmal]e ge- liel~ .cUeselbe aber hereits nach elnem Semester fang, wle er die Brficke yon der Opt i~ zur Elek- winder, um sein Studlum *bel Kundt i:n StraIlgurg trizi~ts]ehre immer welter un~ fester zn sehlagen fortzusetzen. Nie ister mfide gew,orden., des Ein- verm,echte, und win er i~n,s~oesondere in der letz~en flusses dieses re,n. ibm fiber a]les verehrten Zelt noch ger Planckschen S~rah]~n.gstheorie ]~annes in tiefer Dankbarkeit zu geden~:en. Im neue, feste experimente]~e Stiitzen gegel~n hat. ;[ahre ]888 folgte er Kundt naeh Berlin, als In den letzten zwei Jahren ~begann die schlei- dieser als Nachfolger vo~ Helmholtz an die dot- chende Krank~eit die Kr~fte dieses senst so tige Universit~t herufen wurde, und pro'mo-e~erte lehensstarken X annes zu untergr~ben. Abet 1889 tni~ einer Arbelt fiber das Reflexioasver- seinen starken Willen hat des Leiden nieht zu mggen der l~[etalle. Bald darauf wurde er zc~m l~hmen vermoeht, und erst als es ihn wenige 1018 Westphal: Heinrich Rubens. [ Die Natur- kwiss'enschaften Wochen vor seinem Tode endgiiltig auf des Lager zision anstelIte, Ausschl~ge ~eobaehtete, welche wart, hat seine wi,ssensehaftliehe Lehensarbeit oft ~n~dr Bruehteile eines ~[illimeters groJ3 waren i'hren alkufri~en A'bsehl,ufl gefu~den. u,md bis auf i/2o mm g,ena~ abgelesen werden Iteinrich Rubens gehhI'te zxt d,en lViensehen, mu~ten. )~ur der v,om Erkennlni:sdrange ange- deren Leistungen schon zu ihren L.ebzeiten die feuerten auBerordentliehen Energie, die Rubens Anerkennung fan.den, die iimen gebtiahrt. Und so eignete; i,st es za ,d.anken, dab die wissensehaft- sind die ~ulheren E'hrnngen za~h.lreieh, in denen lichen Friiohte seines allzu kurzen Leben.s so diese Anerkennung ihr,en Au.sdrnek fan,& Im wertvolI ~nd so reich .sin& Jahre 1907 wnrde er orden¢Iiches 3gRgtied der So weir .entfern~ Rubens yon jedem Hoehmut PreUflisehen Akademie ,tier Wissensehaften, nnd Gelehrtendiinkel war, .so .sehr war er sieh in der en Beriehten :aueh ,die Meh,rzahl' seiner Ar- doeh der Wfirde bewulht, welehe mR der Stellung .beiten verSffentlicht isd.. .Er wet korresioo,n- nines deutsehen IIoelase,huI'lehrers verbunden ist. dierendes ~[itglied tier Ghttinger Gesellsehaft tier Wie yon sieh selbst, so verlangte er. v,on a.ndern, Wis,senseh.aften, E:hrenmitglied des R,oyal Insti- daJ3 sie .dieser Wiirde in ihrem pershnliehen und tutio.n undl des PhysikMischen Verein, s. Frankfurt wi,ssensehaftliehen VerhaRen Reehnung trfigen. am Nat,n,. Die Universit~ten Ca'mbri.dge .and Leeds Sau~berkeR der 3/[et,hoden war ibm aueh 'bier Be- verliehen ibm die Wfird'e nines. Eihrendoktors. Yon diirfnis. Were er einmal seine Neigung und sei.n der Royal Society wurd~e er ~it der R~umfor, d- Vertrauen geschenkt hare, .dem hint er sein rnedaiI~re au,sgezei,ehnet, von d:er Wiener Akademie Leben Iang in Treue an, moeht,en sich aueh die der Wi.ssensehaften mit dem .Ban'mgartenpreis. gugeren Beziehungen :geloekert ha,ben. Ffir Un- Zeitweilig war er ¥orstand!sra,t des. De'u.t,sehen tre'ue nn& Hinterh~Rig,kei.t h.atte .er kein Ver- 3gaseums in 3gfinehen. Dem Senat der Ber:Iiner st~ndnis, GewalttgGgkeR ekeRe tim an. Win Universit~t hat er gerade in den sehweren Zeiten sehwer meg er noeh kurz vet s.einem Tode wegen unmitte]bar n aeh dem Xrie.ge angehhrt. W~h- des grauenv.ollen Todes seines alten Freu,ndes und rend vieler Jahre war Rubens Vorsit:zerMer der Studiengenossen Walther Rathen, au gelitten Deutsehen Physikalisohen Gesellsehaf~. Hi.er war, haben. ebenso W~e in allen anderen Xhrperseha~ten, denen Wie wenige kannte Rubens den Begriff der er angehhrte, sein EinfluB dnreh die 7tube seines Verehrnng. Seine Verehrung .galt in erster Linie Urteils, win dutch die vermittetnde Art, anit der den lebenden und toten GroBen selner Wi.ssen- er Gegensgtze zu seMichten wulRe, Yon bes,on- sahaft. A'ber seine Pietgt un4 E~arfureht vor .der deter ]~edentung. Tradition maehte aneh vet k];einen Din.gen nieht Die hervorsteehendsten Ziige in Ruben£ Oha- ha]t. An althergebraehten Br~uehen .nnd Dingen, ra$:ter waren .~n.sgepr~igter ~Gereehtigkei%sinn, un& wenn es nur der Oft und die Zeit eincr Ver- ~ewissenhaftlgkeR in Tun unc~ Urteilen, IdeMis- anstalt,nng war, rfittelte er nut .sehr ungern. Wie m~s, Sehliehtheit des Wesens un.d anl?eror;dlent- sehwer hat er sieh z~r Ve,rlegung des Berlfner tlehe, oft. fast iiberfrie'bene BeseheidenheR. Die Koll0quiums aus tier Institutsbi~oliothek m den Ehr.u:ngen u~nd die" Anerkennun:g, die er in .so kleinen IIhrsaal entsehlos, sen. Ieh glaube, so re~ehem Xalhe erfuhr, haben thin gewit~ lq'r.eude reeht wohl hat er sieh dort nie gefiihlt. Selten bereitet, aber Stolz und Dberhehung waren ilhm verfehlte er, einem Besueher, den er zum Sitzen fremd. Stets war er geneigt, "gerdlenste ant anf dem Sofa in seinem Direktorzimmer nhtigte, andere zu sehieben. Wenn ibm eine E ntdeekung z u erz~hlen, dab dort ttelmholtz seinen ~i~tags- getang oder wenn er ei,n,e seiner sehhnen ?¢fessun- s ehlaf zu halten pflegte. Essei n'ur so sehade, fen ~been.det hare, ,so empf:an,d er daran nine leb- dab der are Waehstuehfi'berzag babe erneuert hafte Fr6nde.
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