﻿ACADEMY 
  OF 
  SCIENCES. 
  231 
  

  

  chosen 
  science, 
  observing, 
  collecting, 
  arranging, 
  analyzing, 
  classifyiug, 
  liut 
  also 
  

   a 
  great 
  philosophic 
  thinker— 
  thsxt 
  his 
  life 
  and 
  work 
  form 
  an 
  epoch 
  in 
  science 
  — 
  

   that 
  in 
  looking 
  back 
  over 
  the 
  track 
  of 
  time, 
  his 
  gigantic 
  stature 
  will 
  remain 
  for 
  

   many 
  ages 
  to 
  come 
  a 
  conspicuous 
  landmark. 
  

  

  As 
  we 
  look 
  back 
  over 
  the 
  history 
  of 
  science, 
  we 
  see, 
  at 
  long 
  intervals, 
  certain 
  

   men 
  who 
  seem 
  to 
  tower 
  far 
  above 
  their 
  fellows. 
  In 
  what 
  consists 
  their 
  great- 
  

   ness 
  ? 
  They 
  are 
  men 
  who 
  have 
  introduced 
  great 
  ideas 
  or 
  new 
  methods 
  into 
  

   science 
  — 
  ideas 
  which 
  extend 
  the 
  domain 
  of 
  human 
  thought, 
  or 
  methods 
  which 
  

   increase 
  our 
  power 
  over 
  nature, 
  facilitate 
  the 
  progress 
  of 
  discovery, 
  and 
  thus 
  

   open 
  the 
  way 
  to 
  the 
  conquest 
  of 
  new 
  fields. 
  Such 
  men 
  were 
  Copernicus, 
  and 
  

   Galileo, 
  and 
  Kepler, 
  and 
  Newton, 
  and 
  Herschell, 
  in 
  astronomy 
  : 
  such 
  were 
  Lin- 
  

   naeus, 
  and 
  Buffon, 
  and 
  Cuvier 
  and 
  Agassiz, 
  in 
  organic 
  science. 
  

  

  Let 
  me 
  illustrate 
  the 
  effect 
  of 
  the 
  introduction 
  of 
  great 
  ideas 
  into 
  science. 
  I 
  

   will 
  select 
  one 
  example 
  from 
  astronomy, 
  and 
  one 
  from 
  geology. 
  

  

  Before 
  the 
  time 
  of 
  Copernicus 
  and 
  Galileo, 
  this, 
  our 
  earth, 
  was 
  all 
  of 
  space 
  

   for 
  us. 
  Sun, 
  moon, 
  and 
  stars 
  were 
  but 
  little 
  satellites 
  revolving 
  about 
  us 
  at 
  in- 
  

   considerable 
  distance. 
  Astronomy 
  then 
  was 
  but 
  the 
  geometry 
  of 
  the 
  heavens, 
  

   the 
  geometry 
  of 
  the 
  curious 
  lines 
  traced 
  by 
  these 
  wandering 
  fires 
  on 
  the 
  

   concave 
  board 
  of 
  heaven. 
  But 
  with 
  the 
  first 
  glance 
  through 
  the 
  telescope, 
  the 
  

   phases 
  of 
  Venus 
  and 
  the 
  satellites 
  of 
  Jupiter 
  revealed 
  the 
  existence 
  of 
  other 
  

   worlds 
  beside 
  our 
  own. 
  In 
  that 
  moment 
  the 
  fundamental 
  idea 
  of 
  modern 
  as- 
  

   tronomy, 
  the 
  idea 
  of 
  infinite 
  space 
  filled 
  with 
  worlds 
  like 
  our 
  own, 
  was 
  fully 
  

   born 
  in 
  the 
  mind 
  of 
  Galileo. 
  In 
  that 
  moment 
  the 
  intellectual 
  vision 
  of 
  man 
  

   was 
  infinitely 
  extended. 
  

  

  Again, 
  before 
  the 
  time 
  of 
  Buffon 
  and 
  Cuvier, 
  this, 
  our 
  human 
  epoch, 
  the 
  his- 
  

   tory 
  of 
  our 
  race, 
  was 
  all 
  of 
  tim.e 
  for 
  us. 
  Shells 
  and 
  other 
  remains 
  of 
  marine 
  

   animals 
  had, 
  indeed, 
  been 
  found 
  far 
  in 
  the 
  interior 
  of 
  the 
  continents, 
  and 
  high 
  up 
  

   the 
  slopes 
  of 
  mountains, 
  and 
  there 
  had 
  been 
  much 
  speculation 
  as 
  to 
  the 
  origin 
  

   of 
  these. 
  Some 
  may 
  have 
  thought 
  by 
  means 
  of 
  these 
  to 
  extend 
  the 
  limits 
  of 
  

   our 
  epoch, 
  but 
  none 
  dreamed 
  of 
  other 
  epochs. 
  Some 
  may 
  have 
  thought 
  they 
  

   were 
  discovering 
  new 
  coast 
  islands 
  along 
  the 
  shores 
  of 
  time 
  ; 
  but 
  none 
  dreamed 
  

   that 
  these 
  were 
  the 
  evidences 
  of 
  new 
  worlds 
  in 
  the 
  infinite 
  abyss 
  of 
  time. 
  It 
  

   was 
  reserved 
  for 
  Buffon 
  and 
  Cuvier 
  first 
  to 
  recognize 
  the 
  entire 
  difference 
  be- 
  

   tween 
  fossil 
  and 
  living 
  species. 
  In 
  that 
  moment 
  was 
  born 
  the 
  fundamental 
  

   idea 
  of 
  geology, 
  the 
  idea 
  of 
  infinite 
  time 
  containing 
  many 
  successive 
  epochs, 
  or 
  

   time-worlds 
  like 
  our 
  own. 
  In 
  that 
  moment 
  the 
  intellectual 
  horizon 
  of 
  man 
  was 
  

   again 
  infinitely 
  extended. 
  

  

  These 
  two 
  are 
  the 
  grandest 
  moments 
  in 
  the 
  history 
  of 
  science 
  ; 
  yea, 
  in 
  the 
  

   intellectual 
  history 
  of 
  our 
  race. 
  The 
  one 
  opened 
  the 
  gates 
  of 
  infinite 
  space, 
  

   and 
  showed 
  us 
  many 
  space 
  worlds 
  ; 
  the 
  other 
  opened 
  up 
  the 
  gates 
  of 
  infinite 
  

   time, 
  and 
  showed 
  us 
  as 
  many 
  successive 
  creations 
  or 
  time-worlds. 
  

  

  We 
  see, 
  then, 
  the 
  intellectual 
  impulse 
  communicated 
  by 
  a 
  great 
  new 
  idea. 
  

   The 
  introduction 
  of 
  a 
  new 
  method, 
  though 
  less 
  striking 
  to 
  the 
  imagination, 
  is 
  

   perhaps 
  even 
  more 
  important. 
  We 
  will 
  illustrate 
  it 
  presently. 
  Now, 
  I 
  wish 
  to 
  

   show 
  that 
  Agassiz, 
  too, 
  was 
  the 
  originator 
  of 
  new 
  ideas, 
  and 
  the 
  introducer, 
  or 
  

  

  