﻿268 
  ANNUAL 
  REPORT 
  SMITHSONIAN 
  INSTITUTION, 
  1927 
  

  

  earth's 
  surface 
  independent 
  of 
  that 
  within. 
  The 
  temperature 
  of 
  the 
  

   earth's 
  surface 
  has 
  in 
  no 
  way 
  become 
  permanently 
  lower; 
  instead 
  it 
  

   shows 
  rythmical 
  changes. 
  The 
  great 
  ice 
  ages 
  of 
  the 
  earth's 
  history 
  

   stand 
  in 
  close 
  relationship 
  with 
  mountain 
  ranges 
  brought 
  into 
  exist- 
  

   ence 
  through 
  foldings. 
  For 
  the 
  Dyas 
  and 
  the 
  Diluvian 
  ice 
  periods, 
  

   at 
  least, 
  the 
  dependence 
  is 
  clear. 
  Apart 
  from 
  orographic 
  and 
  cos- 
  

   mical 
  causes 
  the 
  rhythms 
  of 
  the 
  temperature 
  depend 
  upon 
  the 
  

   rhythmical 
  feeding 
  into 
  the 
  atmosphere 
  of 
  carbon 
  dioxide 
  of 
  volcanic 
  

   origin 
  as 
  well 
  as 
  upon 
  the 
  varying 
  need 
  of 
  this 
  gas 
  in 
  the 
  formation 
  

   of 
  coal 
  and 
  the 
  carbonate 
  rocks. 
  Arrhenius 
  and 
  Freeh 
  have 
  noted 
  

   the 
  rhythm 
  of 
  these 
  carbon-dioxide 
  periods 
  and 
  shown 
  their 
  geo- 
  

   logical 
  importance. 
  To-day, 
  through 
  the 
  consumption 
  of 
  the 
  coal 
  

   beds 
  by 
  man 
  in 
  his 
  industries, 
  a 
  new 
  enrichment 
  of 
  the 
  atmosphere 
  

   wath 
  carbon-dioxide 
  is 
  taking 
  place. 
  He 
  also 
  thereby 
  wards 
  off 
  the 
  

   remote 
  danger 
  of 
  the 
  death 
  of 
  the 
  earth 
  through 
  cold.^*' 
  From 
  the 
  

   earth 
  we 
  read 
  no 
  sign 
  of 
  danger 
  that 
  the 
  oceans 
  and 
  rivers 
  may 
  

   become 
  solid 
  ice 
  nor 
  that 
  carbon-dioxide 
  snow 
  will 
  fall, 
  nor 
  yet 
  that 
  

   the 
  earth, 
  at 
  a 
  temperature 
  of 
  absolute 
  zero, 
  will 
  be 
  covered 
  by 
  a 
  now 
  

   ocean 
  of 
  liquid 
  oxygen 
  and 
  liquid 
  nitrogen, 
  while 
  only 
  hydrogen 
  

   and 
  helium 
  will 
  form 
  the 
  last 
  tenuous 
  atmosphere 
  of 
  the 
  dead 
  earth. 
  

   The 
  natural 
  deliverer 
  of 
  this 
  incomparably 
  important 
  breath 
  of 
  

   life 
  constituted 
  by 
  the 
  carbon 
  dioxide 
  of 
  the 
  atmosphere, 
  together 
  

   with 
  the 
  rich 
  store 
  of 
  the 
  gas 
  dissolved 
  in 
  the 
  waters 
  of 
  the 
  oceans, 
  is 
  

   vulcanism. 
  Besides 
  the 
  seismical 
  tremblings 
  of 
  the 
  earth's 
  crust 
  vol- 
  

   canic 
  actions 
  give 
  us 
  the 
  most 
  immediate 
  evidence 
  of 
  the 
  earth's 
  life. 
  

   Their 
  manifestations, 
  the 
  movements 
  of 
  the 
  glowing 
  liquid 
  masses 
  

   toward 
  the 
  earth's 
  surface, 
  together 
  with 
  the 
  accompanying 
  and 
  sub- 
  

   sequent 
  phenomena, 
  are 
  recorded 
  throughout 
  all 
  geological 
  time. 
  

   They 
  do 
  not, 
  however, 
  occur 
  with 
  equal 
  strength 
  or 
  at 
  equal 
  intervals. 
  

   So 
  far 
  as 
  the 
  outcropping 
  of 
  the 
  volcanic 
  phenomena 
  of 
  the 
  past 
  is 
  to 
  

   be 
  dated 
  — 
  and 
  this 
  not 
  in 
  every 
  case 
  with 
  the 
  desired 
  accuracy 
  — 
  the 
  

   uprising 
  and 
  the 
  eruptions 
  of 
  volcanic 
  masses 
  cluster 
  about 
  the 
  times 
  

   of 
  the 
  great 
  mountain-building 
  foldings. 
  They 
  were 
  generally 
  closely 
  

   connected, 
  as 
  is 
  the 
  case 
  even 
  to-day, 
  with 
  the 
  mobile 
  regions 
  where 
  

   this 
  building 
  of 
  mountains 
  was 
  taking 
  place 
  through 
  foldings, 
  and 
  

   occurred 
  either 
  near 
  them 
  or 
  within 
  them, 
  or 
  else 
  in 
  regions 
  of 
  active 
  

   movements 
  of 
  the 
  ground. 
  As 
  an 
  expression 
  of 
  the 
  life 
  of 
  the 
  earth 
  

   the 
  rhythmical 
  character 
  of 
  the 
  phenomena 
  of 
  vulcanism 
  is 
  convinc- 
  

   ing. 
  How 
  does 
  the 
  intensity 
  of 
  the 
  volcanic 
  activity 
  of 
  the 
  present 
  

  

  '" 
  Doctor 
  Abbot 
  Las 
  shown 
  tluit 
  as 
  long 
  as 
  there 
  is 
  anything 
  like 
  the 
  present 
  amount 
  

   of 
  water 
  vapor 
  in 
  the 
  earth's 
  atmosphere 
  the 
  effect 
  of 
  carbon 
  dioxide 
  just 
  discussed 
  will 
  

   be 
  nullified 
  by 
  the 
  overwhelmingly 
  greater 
  similar 
  effect 
  of 
  water 
  vapor. 
  (Note 
  by 
  

   translator.) 
  

  

  