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  XXL 
  — 
  On 
  the 
  Total 
  Eclipse 
  of 
  the 
  Sun, 
  on 
  July 
  28, 
  1851, 
  observed 
  at 
  Goteborg 
  ; 
  

   with 
  a 
  description 
  of 
  a 
  new 
  Position 
  Micrometer. 
  By 
  William 
  Swan, 
  

   F.R.S.E. 
  

  

  (Read 
  1st 
  December 
  1851.) 
  

  

  Having 
  long 
  desired 
  to 
  witness 
  a 
  total 
  eclipse 
  of 
  the 
  snn, 
  I 
  resolved 
  to 
  proceed 
  

   to 
  some 
  place 
  in 
  the 
  line 
  of 
  the 
  moon's 
  shadow, 
  for 
  the 
  purpose 
  of 
  observing 
  that 
  

   which 
  took 
  place 
  on 
  the 
  28th 
  of 
  last 
  July. 
  

  

  Various 
  reasons 
  induced 
  me 
  to 
  prefer 
  the 
  town 
  of 
  Goteborg 
  in 
  Sweden 
  to 
  any 
  

   other 
  station. 
  It 
  had 
  interesting 
  historical 
  associations 
  connected 
  with 
  eclipses 
  ; 
  

   and 
  there 
  was 
  something 
  pleasing 
  in 
  the 
  prospect 
  of 
  seeing 
  the 
  red 
  prominences, 
  

   which 
  excited 
  so 
  much 
  attention 
  at 
  the 
  eclipse 
  of 
  1842, 
  at 
  the 
  very 
  spot 
  where 
  

   they 
  were 
  observed, 
  probably 
  for 
  the 
  first 
  time, 
  in 
  1733 
  j* 
  but 
  a 
  more 
  import- 
  

   ant 
  ground 
  of 
  preference, 
  was 
  its 
  proximity 
  to 
  the 
  central 
  line 
  of 
  the 
  moon's 
  

   shadow, 
  and 
  its 
  being 
  directly 
  accessible 
  from 
  England. 
  

  

  I 
  accordingly 
  sailed 
  from 
  Hull 
  on 
  the 
  19th 
  July, 
  by 
  the 
  Courier 
  Steamer, 
  and 
  

   reached 
  Goteborg 
  on 
  the 
  24th. 
  Among 
  the 
  passengers 
  were 
  Mr 
  Lassel, 
  Mr 
  

   Adams 
  of 
  Cambridge, 
  Mr 
  Carrington 
  of 
  Durham 
  Observatory, 
  Mr 
  Robert 
  Cham- 
  

   bers 
  and 
  Mr 
  John 
  Adie 
  of 
  Edinburgh, 
  Mr 
  Dunkin 
  of 
  Greenwich 
  Observatory, 
  

   and 
  the 
  Astronomer-Royal. 
  

  

  Mr 
  Airy 
  had 
  determined 
  to 
  observe 
  the 
  eclipse 
  at 
  Goteborg, 
  and 
  at 
  his 
  request 
  

   a 
  meeting 
  was 
  held 
  there 
  on 
  the 
  26th 
  July, 
  when 
  it 
  was 
  agreed 
  by 
  those 
  who 
  

   were 
  present 
  to 
  separate 
  as 
  much 
  as 
  possible, 
  in 
  order 
  to 
  increase 
  the 
  chance 
  of 
  

   at 
  least 
  some 
  one 
  seeing 
  the 
  eclipse, 
  in 
  the 
  event 
  of 
  the 
  weather 
  proving 
  cloudy, 
  — 
  

   a 
  precaution 
  which 
  its 
  unfavourable 
  aspect 
  at 
  that 
  time 
  rendered 
  the 
  more 
  advis- 
  

   able. 
  Professor 
  Chevallier 
  of 
  Durham 
  and 
  Mr 
  John 
  Adie, 
  had 
  previously 
  de- 
  

   termined 
  to 
  observe 
  the 
  eclipse 
  from 
  the 
  roof 
  of 
  their 
  hotel 
  in 
  town. 
  Lieutenant 
  

   Pettersson 
  of 
  the 
  Navigation 
  School 
  of 
  Goteborg, 
  kept 
  by 
  the 
  Observatory 
  of 
  that 
  

   institution. 
  The 
  Astronomer-Royal 
  selected 
  a 
  station 
  to 
  the 
  east 
  of 
  the 
  town, 
  and 
  

   Mr 
  Chambers, 
  one 
  about 
  three 
  miles 
  to 
  the 
  west. 
  I 
  chose 
  for 
  my 
  station 
  a 
  hill 
  

   named 
  Ramberget, 
  situated 
  about 
  a 
  mile 
  to 
  the 
  north 
  of 
  Goteborg, 
  and 
  on 
  the 
  op- 
  

   posite 
  bank 
  of 
  the 
  river. 
  This, 
  being 
  the 
  highest 
  eminence 
  in 
  the 
  neighbourhood 
  of 
  

   the 
  town, 
  commanded 
  an 
  extensive 
  view 
  of 
  the 
  country 
  on 
  every 
  side, 
  and 
  was 
  

   therefore 
  a 
  very 
  favourable 
  station 
  for 
  witnessing 
  the 
  effects 
  produced 
  on 
  the 
  land- 
  

   scape 
  during 
  the 
  eclipse. 
  I 
  referred 
  its 
  position 
  to 
  that 
  of 
  Lieutenant 
  Petters- 
  

   son's 
  Observatory, 
  by 
  the 
  magnetic 
  bearings 
  of 
  several 
  conspicuous 
  objects, 
  taken 
  

   by 
  means 
  of 
  a 
  prismatic 
  compass. 
  {See 
  Table 
  I., 
  page 
  345.) 
  The 
  observations, 
  when 
  

  

  * 
  See 
  Observatio 
  Eclipsis 
  Soils 
  totalis 
  cum 
  mora 
  facta 
  Gothoburgi 
  Svecioz, 
  fyc, 
  a 
  Dom. 
  Birgero 
  

   Vassenio. 
  — 
  Phil. 
  Trans., 
  vol. 
  xxxviii. 
  

  

  VOL. 
  XX. 
  PART 
  III. 
  4 
  Y 
  

  

  