﻿214 
  

  

  ON 
  THE 
  MAGNETIC 
  DIP 
  

  

  at 
  Providence 
  and 
  Albany 
  with 
  the 
  poles 
  direct 
  and 
  reversed, 
  we 
  find 
  

   for 
  the 
  former 
  place, 
  that 
  the 
  observed 
  dip 
  with 
  the 
  poles 
  direct 
  fell 
  

   short 
  of 
  that 
  when 
  they 
  were 
  reversed 
  by 
  1.9 
  minute, 
  and 
  for 
  the 
  latter 
  

   place, 
  that 
  the 
  observed 
  dip 
  with 
  the 
  poles 
  direct 
  exceeded 
  that 
  when 
  

   they 
  were 
  reversed 
  by 
  1.7 
  minute, 
  giving 
  a 
  correction 
  for 
  the 
  eccen- 
  

   tricity 
  of 
  the 
  centre 
  of 
  gravity 
  in 
  needle 
  No. 
  1 
  of 
  -f- 
  0.9 
  minute. 
  For 
  

   needle 
  No. 
  2 
  the 
  same 
  correction 
  obtained 
  from 
  the 
  New 
  York 
  obser- 
  

   vations, 
  where 
  the 
  poles 
  were 
  reversed 
  next 
  before 
  the 
  Springfield 
  

   observations, 
  and 
  from 
  those 
  at 
  Albany, 
  where 
  they 
  were 
  reversed 
  next 
  

   after 
  the 
  Springfield 
  results, 
  is 
  -f- 
  4.3 
  minutes 
  and 
  -{-3.9 
  minutes, 
  the 
  

   mean 
  being 
  + 
  4.1 
  minutes. 
  The 
  error 
  from 
  not 
  reversing 
  the 
  poles 
  

   is 
  thus 
  probably 
  reduced 
  to 
  less 
  than 
  one 
  minute. 
  

  

  The 
  place 
  of 
  observation 
  was 
  in 
  the 
  yard 
  attached 
  to 
  the 
  Hamden 
  

   Coffee-house 
  Hotel. 
  The 
  latitude 
  of 
  Springfield, 
  as 
  stated 
  by 
  Mr 
  Paine, 
  

   is 
  42° 
  05' 
  58" 
  N., 
  and 
  the 
  longitude 
  72° 
  36' 
  W. 
  

  

  Needle. 
  

  

  Dip. 
  

  

  Temp. 
  

  

  Date 
  of 
  Observation. 
  

  

  Place. 
  

  

  Observer. 
  

  

  Weather. 
  

  

  No. 
  1, 
  

  

  74°02'.8 
  

  

  68° 
  

  

  August 
  8, 
  1834, 
  

   10h 
  P.M. 
  

  

  Providence. 
  

  

  A.D.Bache. 
  

  

  Clear. 
  Wind 
  

   S. 
  and 
  S. 
  W. 
  

  

  No. 
  1, 
  

   Do. 
  corrected, 
  

  

  No. 
  2, 
  

   Do. 
  corrected, 
  

   Mean 
  corrected, 
  

  

  74 
  01 
  .1 
  

   74 
  02.0 
  

   74 
  15.3 
  

   74 
  09.4 
  

   74 
  10.7 
  

  

  65 
  

  

  August 
  10, 
  1834, 
  

   8 
  A.M. 
  

  

  Springfield. 
  

  

  A. 
  D.Bache. 
  

  

  Cloudy. 
  

   Wind 
  N. 
  E. 
  

  

  MAGNETIC 
  DIP 
  AT 
  ALBANY, 
  NEW 
  YORK. 
  

  

  The 
  observations 
  at 
  this 
  place 
  with 
  the 
  two 
  needles 
  were 
  divided 
  by 
  

   a 
  severe 
  thunder 
  storm, 
  which 
  however 
  lasted 
  but 
  fifteen 
  minutes. 
  

   The 
  facilities 
  for 
  observation 
  were 
  perhaps 
  counterbalanced 
  by 
  this 
  

   circumstance. 
  After 
  due 
  examination 
  of 
  the 
  positions 
  which 
  Profes- 
  

   sor 
  Henry 
  had 
  occupied 
  for 
  similar 
  observations 
  ; 
  the 
  want 
  of 
  a 
  proper 
  

   shelter, 
  and 
  other 
  circumstances 
  connected 
  with 
  changes 
  made 
  since 
  

   the 
  date 
  referred 
  to, 
  induced 
  the 
  preference 
  of 
  a 
  station 
  in 
  the 
  lower 
  

   part 
  of 
  the 
  town, 
  in 
  rear 
  of 
  Foot's 
  hotel. 
  

  

  The 
  latitude 
  of 
  Albany 
  is 
  42° 
  39' 
  03"N., 
  longitude 
  73° 
  44' 
  49" 
  W. 
  

  

  