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  COLLECTION 
  OF 
  OBSERVATIONS 
  ON 
  THE 
  

  

  Observations 
  on 
  the 
  Eclipse 
  of 
  the 
  Sun 
  November 
  30th, 
  1834, 
  made 
  at 
  Friends' 
  Observatory, 
  

   Fourth 
  Street, 
  Philadelphia. 
  By 
  Joseph 
  Roberts, 
  Jun. 
  

  

  The 
  morning 
  was 
  clear 
  and 
  without 
  clouds 
  till 
  about 
  eleven 
  o'clock, 
  

   when 
  the 
  eastern, 
  western 
  and 
  southern 
  sky 
  became 
  overcast 
  with 
  thin 
  

   white 
  clouds 
  moving 
  from 
  the 
  west. 
  At 
  noon 
  determined 
  the 
  state 
  of 
  

   the 
  clock 
  by 
  the 
  fixed 
  transit 
  instrument. 
  The 
  beginning 
  of 
  the 
  

   eclipse, 
  observed 
  with 
  an 
  achromatic 
  telescope 
  with 
  a 
  power 
  of 
  about 
  

   38, 
  happened 
  at 
  1 
  h. 
  m. 
  15.85 
  sec. 
  mean 
  civil 
  time, 
  corrected 
  for 
  

   the 
  rate 
  of 
  the 
  clock, 
  determined 
  by 
  transits 
  both 
  before 
  and 
  after 
  the 
  

   eclipse. 
  The 
  observation 
  of 
  the 
  beginning 
  was 
  very 
  good 
  ; 
  but 
  from 
  a 
  

   few 
  minutes 
  after 
  the 
  beginning 
  till 
  some 
  time 
  after 
  the 
  end 
  of 
  the 
  eclipse 
  

   there 
  was 
  a 
  constant 
  succession 
  of 
  clouds 
  between 
  the 
  sun 
  and 
  the 
  

   observer, 
  often 
  so 
  dense 
  as 
  to 
  render 
  the 
  sun 
  invisible 
  ; 
  at 
  the 
  time 
  

   of 
  the 
  greatest 
  obscuration 
  the 
  sun 
  was 
  visible 
  through 
  thin 
  clouds. 
  

   Determined 
  the 
  magnitude 
  of 
  the 
  eclipse 
  when 
  compared 
  with 
  a 
  mea- 
  

   sure 
  of 
  the 
  sun's 
  diameter, 
  taken 
  with 
  a 
  Troughton 
  micrometer 
  near 
  

   noon 
  of 
  the 
  same 
  day. 
  The 
  obscured 
  part 
  measured 
  10.755 
  digits, 
  

   which 
  diners 
  from 
  the 
  calculation 
  about 
  a 
  three 
  hundredth 
  part 
  of 
  a 
  

   digit, 
  or 
  five 
  seconds. 
  This 
  observation 
  was 
  made 
  under 
  unfavourable 
  

   circumstances. 
  The 
  end 
  of 
  the 
  eclipse 
  happened 
  at 
  3 
  h. 
  37 
  m. 
  45 
  sec. 
  

   mean 
  time 
  corrected. 
  A 
  haze 
  about 
  the 
  sun 
  may 
  have 
  caused 
  the 
  

   disappearance 
  of 
  the 
  moon 
  a 
  few 
  seconds 
  before 
  the 
  actual 
  end 
  of 
  the 
  

   eclipse, 
  in 
  which 
  case 
  the 
  latter 
  number 
  should 
  be 
  increased 
  a 
  few 
  

   seconds. 
  

  

  Observations 
  on 
  the 
  Solar 
  Eclipse 
  of 
  November 
  30th, 
  1834, 
  made 
  at 
  Philadelphia 
  and 
  Ger- 
  

   mantown, 
  Pennsylvania. 
  Communicated 
  by 
  S. 
  C. 
  Walker. 
  

  

  The 
  following 
  observations 
  of 
  the 
  Solar 
  Eclipse 
  of 
  November 
  30th 
  

   have 
  been 
  communicated 
  to 
  me 
  by 
  the 
  respective 
  observers. 
  They 
  

   are 
  all 
  expressed 
  in 
  mean 
  solar 
  time 
  of 
  the 
  Hall 
  of 
  Independence, 
  lon- 
  

   gitude 
  5 
  h. 
  m. 
  43.9 
  sec, 
  latitude 
  39° 
  56' 
  59". 
  

  

  