﻿454 
  MR 
  WILLIAM 
  SWAN 
  ON 
  THE 
  

  

  made 
  from 
  memory, 
  or 
  hastily 
  sketched 
  during 
  the 
  totality 
  ; 
  there 
  seems 
  suffi- 
  

   cient 
  resemblance 
  between 
  them, 
  to 
  shew 
  that 
  they 
  all 
  represent 
  the 
  same 
  object.* 
  

   But 
  here 
  again, 
  if 
  the 
  differences 
  in 
  the 
  drawings 
  are 
  thought 
  sufficient 
  to 
  shew 
  

   that 
  the 
  objects 
  were 
  optical 
  phenomena, 
  — 
  differently 
  delineated 
  by 
  the 
  observers, 
  

   because 
  their 
  forms 
  actually 
  varied 
  when 
  seen 
  at 
  different 
  stations, 
  — 
  it 
  will 
  be 
  

   found 
  that 
  the 
  difficulties 
  are 
  as 
  great 
  as 
  before. 
  

  

  If 
  the 
  figures 
  given 
  by 
  Mr 
  Lassell, 
  Mr 
  Williams, 
  and 
  Mr 
  Stannistreet 
  

   (See 
  fig. 
  9, 
  Nos. 
  1, 
  2, 
  3), 
  who 
  observed 
  from 
  the 
  windows 
  of 
  the 
  same 
  house, 
  

   be 
  compared, 
  it 
  will 
  be 
  found 
  that 
  they 
  exhibit 
  as 
  great 
  inconsistencies 
  as 
  

   any 
  of 
  the 
  other 
  drawings 
  : 
  for 
  all 
  assign 
  to 
  the 
  hook-shaped 
  prominence 
  different 
  

   forms 
  ; 
  and 
  while 
  Mr 
  Williams 
  did 
  not 
  see 
  the 
  detached 
  prominence, 
  nor 
  Mr 
  

   Lassell 
  the 
  low 
  one, 
  Mr 
  Stannistreet 
  saw 
  both. 
  Again, 
  Professor 
  Chevallier 
  

   and 
  Mr 
  Adie 
  (See 
  fig. 
  9, 
  Nos. 
  4 
  and 
  5), 
  who 
  observed 
  from 
  the 
  roof 
  of 
  the 
  

   same 
  house, 
  differ 
  greatly 
  in 
  the 
  delineation 
  of 
  the 
  hook-shaped 
  prominence 
  ; 
  

   for 
  while 
  the 
  latter 
  saw 
  the 
  detached 
  prominence, 
  the 
  former 
  did 
  not 
  see 
  it. 
  

   Lieutenant 
  Pettersson 
  also, 
  who 
  was 
  scarcely 
  a 
  mile 
  distant 
  from 
  them, 
  

   gives 
  a 
  figure 
  of 
  the 
  hook-shaped 
  prominence 
  totally 
  unlike 
  their 
  drawings 
  

   (See 
  No. 
  6). 
  Contrasted 
  with 
  this, 
  we 
  have 
  Mr 
  Airy's 
  and 
  Mr 
  Chevallier's 
  

   drawings 
  agreeing 
  well 
  with 
  that 
  of 
  Mr 
  Williams 
  (See 
  Nos. 
  7, 
  4, 
  and 
  2), 
  who 
  

   was 
  distant 
  40 
  miles 
  from 
  them 
  ; 
  and 
  Mr 
  Hind's 
  and 
  Mr 
  Dawes' 
  resemble 
  closely 
  

   my 
  own 
  (fig. 
  9, 
  Nos. 
  8 
  and 
  9, 
  and 
  fig. 
  8), 
  although 
  we 
  observed 
  at 
  a 
  distance 
  of 
  

   nearly 
  100 
  miles. 
  In 
  this 
  case, 
  then, 
  as 
  formerly, 
  the 
  optical 
  hypothesis 
  is 
  of 
  no 
  

   service 
  in 
  reconciling 
  discrepancies 
  between 
  the 
  observations 
  ; 
  for 
  we 
  have 
  the 
  

   observations 
  agreeing, 
  where 
  on 
  that 
  hypothesis 
  we 
  should 
  expect 
  them 
  to 
  differ, 
  

   and 
  differing 
  where 
  they 
  ought 
  to 
  agree. 
  

  

  It 
  thus 
  appears, 
  that 
  any 
  objections 
  to 
  the 
  hypothesis, 
  that 
  the 
  prominences 
  

   are 
  objects 
  existing 
  in 
  the 
  sun 
  or 
  moon, 
  founded 
  on 
  a 
  want 
  of 
  agreement 
  in 
  the 
  

   observed 
  angles 
  of 
  position, 
  and 
  in 
  the- 
  forms 
  assigned 
  to 
  those 
  objects, 
  apply 
  

   with 
  at 
  least 
  equal 
  force 
  to 
  the 
  hypotheses 
  that 
  they 
  are 
  optical 
  phenomena 
  ; 
  

   while 
  it 
  has 
  already 
  been 
  shewn, 
  that 
  the 
  latter 
  hypotheses 
  labour 
  under 
  insur- 
  

   mountable 
  difficulties 
  peculiar 
  to 
  themselves. 
  The 
  objections 
  to 
  the 
  idea, 
  that 
  

   the 
  prominences 
  are 
  material 
  objects 
  being 
  thus 
  more 
  than 
  neutralised, 
  the 
  coin- 
  

   cidence 
  in 
  the 
  observations 
  of 
  position 
  at 
  tolerably 
  distant 
  stations 
  in 
  cases 
  

   where 
  the 
  angles 
  were 
  carefully 
  ascertained, 
  affords 
  the 
  undiminished 
  weight 
  of 
  

  

  * 
  While 
  the 
  causes 
  now 
  enumerated 
  account 
  sufficiently 
  for 
  much 
  of 
  the 
  general 
  diversity 
  in 
  the 
  

   representations 
  of 
  the 
  hook-shaped 
  prominence, 
  there 
  are 
  at 
  the 
  same 
  time 
  certain 
  different 
  types 
  of 
  

   form 
  which 
  may 
  he 
  ohserved 
  among 
  the 
  drawings, 
  and 
  which 
  can 
  scarcely 
  he 
  referred 
  to 
  these 
  causes. 
  

   On 
  comparing 
  Nos. 
  2, 
  4, 
  7 
  with 
  Nos. 
  8, 
  9, 
  fig. 
  9, 
  and 
  also 
  with 
  fig. 
  8, 
  it 
  will 
  he 
  seen 
  that 
  the 
  first 
  

   three 
  drawings 
  are 
  very 
  like 
  each 
  other, 
  as 
  are 
  also 
  the 
  last 
  three, 
  while 
  there 
  is 
  little 
  resemblance 
  

   between 
  the 
  two 
  sets. 
  The 
  first 
  three 
  represent 
  the 
  hook-shaped 
  prominence 
  as 
  seen 
  through 
  rather 
  

   lai'ge 
  telescopes 
  ; 
  the 
  second, 
  through 
  small 
  ones 
  ; 
  and, 
  as 
  it 
  is 
  well 
  known 
  that 
  certain 
  telescopic 
  

   objects 
  vary 
  greatly 
  in 
  appearance 
  according 
  to 
  the 
  instrumental 
  power 
  brought 
  to 
  bear 
  on 
  them, 
  it 
  

   may 
  be 
  worth 
  inquiry, 
  whether 
  the 
  same 
  is 
  not 
  also 
  the 
  case 
  with 
  the 
  red 
  prominences. 
  

  

  