﻿JAN. 
  19, 
  1922 
  LAMBERT: 
  LATITUDE 
  OF 
  UKIAH 
  39 
  

  

  ground 
  and 
  Cincinnati 
  is 
  subject 
  to 
  a 
  large 
  probable 
  error. 
  A 
  little 
  

   consideration 
  will 
  show, 
  however, 
  that 
  an 
  explanation 
  of 
  the 
  kind 
  

   supposed 
  that 
  is 
  numerically 
  adapted 
  to 
  fit 
  Gaithersburg 
  as 
  well 
  as 
  the 
  

   other 
  stations 
  except 
  Ukiah 
  must 
  be 
  a 
  passable 
  fit 
  for 
  Ukiah 
  also. 
  

  

  The 
  deduced 
  shifting 
  of 
  the 
  Pole 
  must 
  be 
  considered 
  as 
  limited 
  to 
  the 
  

   period 
  discussed, 
  the 
  years 
  1900-1917, 
  inclusive. 
  No 
  examination 
  has 
  

   been 
  made 
  of 
  earlier 
  records 
  to 
  see 
  whether 
  such 
  a 
  shifting 
  might 
  have 
  

   taken 
  place 
  in 
  the 
  past, 
  and 
  until 
  the 
  causes 
  of 
  such 
  a 
  shifting 
  have 
  

   been 
  found 
  it 
  is 
  unwise 
  to 
  predict 
  the 
  future. 
  In 
  regard 
  to 
  the 
  past, 
  

   it 
  is 
  interesting 
  to 
  note 
  that 
  a 
  polar 
  shifting 
  of 
  this 
  sort 
  and 
  about 
  

   this 
  magnitude 
  might 
  have 
  gone 
  on 
  during 
  the 
  whole 
  historical 
  period 
  

   without 
  changing 
  the 
  climate 
  perceptibly. 
  If 
  we 
  put 
  the 
  historical 
  

   period 
  at 
  10,000 
  years 
  in 
  round 
  numbers, 
  the 
  maximum 
  change 
  of 
  

   latitude 
  during 
  that 
  time 
  is 
  less 
  than 
  a 
  mile. 
  It 
  might 
  perhaps 
  be 
  

   possible 
  for 
  a 
  change 
  of 
  this 
  particular 
  sort, 
  namely 
  along 
  the 
  meridian 
  

   of 
  77 
  ° 
  West, 
  to 
  have 
  gone 
  on 
  since 
  the 
  beginning 
  of 
  modern 
  astronomy 
  

   of 
  precision 
  — 
  ^say 
  since 
  Bessel's 
  time 
  — 
  ^without 
  being 
  noticed, 
  simply 
  

   because 
  the 
  longest 
  series 
  of 
  accurate 
  records 
  are 
  in 
  central 
  or 
  western 
  

   Europe, 
  regions 
  which 
  are 
  on 
  meridians 
  nearly 
  at 
  right 
  angles 
  to 
  the 
  

   line 
  of 
  displacement 
  and 
  which 
  therefore 
  undergo 
  a 
  relatively 
  small 
  

   change 
  of 
  latitude. 
  

  

  It 
  is 
  of 
  interest 
  to 
  consider 
  the 
  possible 
  causes 
  for 
  such 
  a 
  displacement 
  

   of 
  the 
  Pole. 
  A 
  little 
  calculation 
  shows 
  that 
  the 
  shifting 
  of 
  mass 
  due 
  

   to 
  erosion 
  and 
  deposition 
  of 
  all 
  sorts, 
  even 
  on 
  the 
  most 
  favorable 
  

   hypotheses, 
  is 
  quite 
  insufficient 
  to 
  produce 
  a 
  shifting 
  of 
  0".0050 
  a 
  year 
  

   in 
  the 
  direction 
  of 
  the 
  earth's 
  axis 
  within 
  its 
  mass. 
  Theories 
  postu- 
  

   lating 
  large 
  departures 
  of 
  the 
  Pole 
  from 
  its 
  present 
  position 
  have 
  been 
  

   much 
  in 
  favor 
  with 
  certain 
  geologists 
  but 
  seem 
  fantastic 
  to 
  mathema- 
  

   ticians 
  and 
  astronomers. 
  An 
  interesting 
  criticism 
  of 
  these 
  theories 
  

   is 
  to 
  be 
  found 
  in 
  an 
  article 
  by 
  the 
  late 
  Professor 
  Barrell.^^ 
  The 
  classic 
  

   paper 
  on 
  this 
  subject 
  from 
  the 
  mathematical 
  point 
  of 
  view 
  is 
  by 
  

   Darwin. 
  ^2 
  ^ 
  shifting 
  of 
  the 
  Pole 
  may 
  be 
  brought 
  about 
  by 
  wide- 
  

   spread 
  though 
  slight 
  elevations 
  and 
  subsidences 
  of 
  the 
  Earth's 
  crust. 
  

   On 
  the 
  most 
  favorable 
  assumption 
  that 
  seemed 
  in 
  any 
  way 
  plausible 
  

   from 
  a 
  geological 
  point 
  of 
  view, 
  Darwin 
  found 
  a 
  possible 
  displacement 
  

   of 
  from 
  1° 
  to 
  3° 
  in 
  any 
  one 
  geological 
  period. 
  The 
  term 
  "geological 
  

   period" 
  is 
  conveniently 
  vague 
  as 
  a 
  unit 
  of 
  time, 
  but 
  if 
  we 
  take 
  a 
  geolog- 
  

  

  ^^ 
  J. 
  Barrell. 
  The 
  status 
  of 
  the 
  hypothesis 
  of 
  polar 
  wanderings. 
  Science 
  40: 
  333. 
  1914. 
  

   '^ 
  G. 
  H. 
  Darwin. 
  On 
  the 
  influence 
  of 
  geological 
  changes 
  on 
  the 
  Earth's 
  axis 
  of 
  rotation, 
  

   Phil. 
  Trans. 
  Roy. 
  Soc. 
  Lond. 
  I. 
  167: 
  271. 
  1877. 
  Or 
  Scientific 
  Papers 
  3: 
  1. 
  

  

  