﻿118 
  NEW 
  YORK 
  STATE 
  MD8EUM 
  

  

  tissue. 
  As 
  the 
  primeval 
  temperature 
  fell, 
  the 
  acid 
  atmosphere 
  

   would 
  react 
  on 
  the 
  lava-like 
  crust 
  and 
  where 
  the 
  temperature 
  fell 
  

   below 
  the 
  boiling 
  point 
  of 
  the 
  acids 
  which 
  composed 
  the 
  atmos- 
  

   phere, 
  the 
  water 
  of 
  the 
  globe 
  would 
  be 
  highly 
  charged 
  with 
  salts 
  

   resulting 
  from 
  the 
  chemical 
  action. 
  With 
  the 
  continued 
  fall 
  of 
  

   temperature 
  the 
  chlorine 
  and 
  sulphur 
  would 
  be 
  gradually 
  removed 
  

   from 
  the 
  atmosphere 
  until 
  the 
  composition 
  of 
  the 
  latter 
  became 
  

   similar 
  to 
  that 
  of 
  the 
  present 
  day, 
  though 
  containing 
  more 
  car- 
  

   bonic 
  acid 
  gas. 
  

  

  This 
  chapter 
  in 
  the 
  earth's 
  history 
  has 
  been 
  so 
  well 
  translated 
  

   by 
  the 
  aid 
  of 
  chemical 
  science 
  that 
  there 
  is 
  no 
  reason 
  to 
  question 
  

   its 
  accuracy, 
  but 
  we 
  do 
  not 
  know 
  in 
  detail 
  the 
  history 
  of 
  the 
  mas- 
  

   sive 
  rocks 
  and 
  gneisses 
  which 
  are 
  now 
  the 
  oldest 
  formations 
  

   known. 
  It 
  also 
  is 
  probable 
  that 
  a 
  long 
  period 
  of 
  time 
  elapsed 
  be- 
  

   tween 
  the 
  formation 
  of 
  the 
  primeval 
  ocean 
  and 
  the 
  dawn 
  of 
  life 
  

   therein. 
  Science 
  has 
  not 
  yet 
  taught 
  us 
  how 
  to 
  measure 
  the 
  length 
  

   of 
  this 
  period 
  or 
  how 
  to 
  recognize 
  the 
  details 
  of 
  earth-building 
  

   which 
  occurred 
  in 
  it. 
  

  

  Present 
  Condition 
  of 
  the 
  Earth's 
  Interior 
  

  

  It 
  has 
  been 
  found 
  by 
  observations 
  taken 
  in 
  deep 
  mines 
  and 
  

   wells 
  that 
  in 
  going 
  toward 
  the 
  center 
  of 
  the 
  earth, 
  the 
  tempera- 
  

   ture 
  increases 
  approximately 
  at 
  the 
  ratio 
  of 
  1 
  degree 
  Fahrenheit 
  

   to 
  51 
  feet 
  of 
  depth.* 
  At 
  this 
  rate, 
  a 
  temperature 
  would 
  prevail 
  

   at 
  the 
  depth 
  of 
  50 
  miles 
  at 
  which 
  all 
  known 
  substances 
  would 
  

   be 
  fused. 
  On 
  this 
  basis 
  rests 
  the 
  theory 
  of 
  a 
  molten 
  interior, 
  

   which 
  is 
  corroborated 
  by 
  various 
  volcanic 
  phenomena. 
  All 
  

   through 
  the 
  historic 
  period 
  and 
  through 
  long 
  geologic 
  ages 
  

   before, 
  volcanoes 
  have 
  poured 
  out 
  from 
  subterranean 
  sources 
  

   vast 
  quantities 
  of 
  molten 
  rock. 
  Physicists 
  who 
  have 
  inves- 
  

   tigated 
  this 
  matter 
  claim 
  that 
  if 
  the 
  interior 
  of 
  the 
  earth 
  

   were 
  fluid, 
  the 
  crust 
  would 
  yield 
  to 
  the 
  attraction 
  of 
  the 
  

   moon 
  and 
  that 
  the 
  phenomena 
  of 
  tides 
  would 
  occur 
  within 
  the 
  

   earth 
  itself. 
  It 
  also 
  appears 
  that 
  the 
  great 
  pressure 
  on 
  the 
  in- 
  

   ternal 
  mass 
  must 
  keep 
  it 
  in 
  a 
  condition 
  of 
  solidity. 
  In 
  this 
  con- 
  

   nection 
  it 
  is 
  pointed 
  out 
  that 
  volcanic 
  phenomena 
  occur 
  along 
  

  

  * 
  Tbeextreme 
  rat 
  if 
  s 
  are 
  1-^-40 
  and 
  1 
  -i- 
  80. 
  

  

  