﻿192 
  ANNUAL 
  REPORT 
  SMITHSONIAN 
  INSTITUTION, 
  1927 
  

  

  tif 
  ul 
  products 
  of 
  nineteeth-century 
  thinlring 
  and 
  experimenting 
  ; 
  then 
  

   he 
  had 
  traced 
  the 
  development 
  in 
  the 
  middle 
  of 
  the 
  century 
  of 
  the 
  

   greatest 
  and 
  most 
  fundamental 
  generalization 
  of 
  all 
  science, 
  the 
  prin- 
  

   ciple 
  of 
  the 
  conservation 
  of 
  energy; 
  then 
  he 
  had- 
  spoken 
  of 
  the 
  estab- 
  

   lishment 
  in 
  the 
  first 
  two 
  decades 
  of 
  the 
  second 
  half 
  of 
  the 
  century 
  of 
  

   the 
  second 
  law 
  of 
  thermodynamics, 
  the 
  principle 
  of 
  entropy 
  or 
  of 
  the 
  

   degradation 
  of 
  energy, 
  and 
  finally 
  of 
  the 
  development 
  by 
  Maxwell 
  of 
  

   the 
  electromagnetic 
  theory 
  and 
  its 
  experimental 
  verification 
  by 
  Hertz 
  

   in 
  1888, 
  only 
  five 
  years 
  earlier 
  than 
  the 
  date 
  of 
  the 
  lecture. 
  This 
  

   theory 
  abolished 
  in 
  all 
  particulars 
  except 
  wave 
  length 
  the 
  distinc- 
  

   tion 
  between 
  light 
  and 
  radiant 
  heat 
  and 
  long 
  electromagnetic 
  waves, 
  

   all 
  these 
  phenomena 
  being 
  included 
  under 
  the 
  general 
  head 
  of 
  the 
  

   physics 
  of 
  the 
  ether. 
  

  

  Then, 
  summarizing 
  this 
  wonderfully 
  complete, 
  well-verified, 
  and 
  

   apparently 
  all-inclusive 
  set 
  of 
  laws 
  and 
  principles 
  into 
  which 
  it 
  

   seemed 
  that 
  all 
  physical 
  phenomena 
  must 
  forever 
  fit, 
  the 
  speaker 
  

   concluded 
  that 
  it 
  was 
  probable 
  that 
  all 
  the 
  great 
  discoveries 
  in 
  

   physics 
  had 
  already 
  been 
  made 
  and 
  that 
  future 
  progress 
  was 
  to 
  be 
  

   looked 
  for, 
  not 
  in 
  bringing 
  to 
  light 
  qualitatively 
  new 
  phenomena 
  

   but 
  rather 
  in 
  making 
  more 
  exact 
  quantitative 
  measurements 
  upon 
  

   old 
  phenomena. 
  

  

  Just 
  a 
  little 
  more 
  than 
  one 
  year 
  later 
  and 
  before 
  I 
  had 
  ceased 
  

   pondering 
  over 
  the 
  aforementioned 
  lecture, 
  I 
  was 
  present 
  in 
  Berlin 
  

   on 
  Christmas 
  eve, 
  1895, 
  when 
  Professor 
  Rontgen 
  presented 
  to 
  the 
  

   (T«rman 
  Physical 
  Society 
  his 
  first 
  X-ray 
  photographs. 
  Some 
  of 
  

   them 
  were 
  of 
  the 
  bones 
  of 
  his 
  hand, 
  others 
  of 
  coins 
  and 
  keys 
  photo- 
  

   graphed 
  through 
  the 
  opaque 
  walls 
  of 
  a 
  leather 
  pocketbook, 
  but 
  all 
  

   clearly 
  demonstrating 
  that 
  he 
  had 
  found 
  some 
  strange 
  new 
  rays 
  

   which 
  had 
  the 
  amazing 
  property 
  of 
  penetrating 
  as 
  opaque 
  an 
  object 
  

   as 
  the 
  human 
  body 
  and 
  revealing 
  on 
  a 
  photographic 
  plate 
  the 
  skele- 
  

   ton 
  of 
  a 
  living 
  person. 
  

  

  Here 
  v/as 
  a 
  completely 
  new 
  phenomenon 
  — 
  a 
  qualitatively 
  new 
  dis- 
  

   covery 
  and 
  one 
  having 
  nothing 
  to 
  do 
  with 
  the 
  principles 
  of 
  exact 
  

   measurement. 
  As 
  I 
  listened 
  and 
  as 
  the 
  world 
  listened, 
  we 
  all 
  began 
  

   to 
  see 
  that 
  the 
  nineteenth 
  century 
  physicists 
  had 
  taken 
  themselves 
  

   a 
  little 
  too 
  seriously, 
  that 
  we 
  had 
  not 
  come 
  quite 
  as 
  near 
  sounding 
  

   the 
  depths 
  of 
  the 
  universe, 
  even 
  in 
  the 
  matter 
  of 
  fundamental 
  physi- 
  

   cal 
  principles, 
  as 
  we 
  thought 
  we 
  had. 
  

  

  This 
  was 
  the 
  dramatic 
  introduction, 
  from 
  the 
  standpoint 
  of 
  one 
  

   of 
  the 
  very 
  young 
  stage 
  assistants 
  in 
  the 
  play, 
  to 
  the 
  new 
  period 
  in 
  

   physics. 
  Nobody 
  at 
  that 
  time 
  dreamed, 
  liowever, 
  what 
  an 
  amazing 
  

   number 
  of 
  new 
  phenomena 
  would 
  come 
  to 
  liglit 
  within 
  the 
  next 
  30 
  

   years 
  nor 
  how 
  revolutionary, 
  or, 
  better, 
  how 
  incomprehensible 
  in 
  

   terms 
  of 
  nineteenth 
  century 
  modes 
  of 
  thought 
  some 
  of 
  them 
  would 
  

   be. 
  But 
  at 
  any 
  rate, 
  Rontgen's 
  discovery 
  began 
  to 
  prepare 
  the 
  

  

  