﻿F. 
  H. 
  Bigelow 
  — 
  Solar 
  Corona. 
  9 
  

  

  In 
  making 
  the 
  comparison, 
  it 
  is 
  proper 
  to 
  bear 
  in 
  mind 
  a 
  

   few 
  obvious 
  considerations. 
  The 
  wires 
  that 
  make 
  the 
  rays 
  on 
  

   the 
  model 
  properly 
  represent 
  only 
  stream 
  lines, 
  or 
  portions 
  of 
  

   the 
  streamers 
  of 
  the 
  corona. 
  The 
  curve 
  is 
  true 
  for 
  that 
  part 
  of 
  

   the 
  streamer 
  which 
  springs 
  from 
  the 
  sun 
  at 
  the 
  latitude 
  corre- 
  

   sponding 
  to 
  the 
  axis 
  of 
  the 
  wire. 
  Inasmuch 
  as 
  the 
  coronal 
  

   streamer 
  is 
  large 
  at 
  its 
  base 
  the 
  curvature 
  of 
  the 
  ray 
  must 
  agree 
  

   in 
  all 
  its 
  parts 
  with 
  the 
  lines 
  springing 
  from 
  this 
  region. 
  The 
  

   consequence 
  is 
  that 
  each 
  ray 
  spreads 
  out, 
  as 
  it 
  recedes 
  from 
  the 
  

   sun, 
  to 
  fill 
  all 
  the 
  space 
  occupied 
  by 
  the 
  bounding 
  curves, 
  and 
  

   we 
  see 
  as 
  a 
  result 
  the 
  curious 
  forms 
  of 
  the 
  curves 
  of 
  the 
  cor- 
  

   ona, 
  which 
  are 
  definite 
  and 
  conform 
  to 
  this 
  law. 
  I 
  would 
  pro- 
  

   pose 
  this 
  as 
  a 
  sufficient 
  proof 
  of 
  the 
  truth 
  of 
  the 
  theory, 
  even 
  

   taking 
  it 
  by 
  itself. 
  The 
  rays 
  set 
  into 
  the 
  model 
  do 
  not 
  pretend 
  

   to 
  represent 
  the 
  lines 
  measured 
  for 
  any 
  particular 
  eclipse, 
  be- 
  

   cause 
  it 
  is 
  designed 
  to 
  illustrate 
  the 
  subject 
  only 
  in 
  a 
  general 
  

   way. 
  One 
  ought 
  properly 
  to 
  construct 
  a 
  model 
  for 
  each 
  

   eclipse 
  using 
  the 
  computed 
  (a 
  . 
  0), 
  the 
  coordinates 
  of 
  the 
  base 
  

   of 
  the 
  ray. 
  Then 
  photographing 
  this, 
  a 
  comparison 
  could 
  be 
  

   made 
  between 
  the 
  individual 
  lines. 
  The 
  model 
  does 
  not 
  show 
  

   the 
  nebulous, 
  structureless 
  mass 
  of 
  material, 
  which 
  was 
  proba- 
  

   bly 
  thrown 
  up 
  along 
  these 
  coronal 
  lines, 
  and 
  is 
  going 
  through 
  

   other 
  transformations 
  in 
  its 
  return 
  to 
  the 
  sun. 
  We 
  miss 
  also 
  

   the 
  radiant 
  light 
  which 
  passes 
  through 
  this 
  coronal 
  matter 
  and 
  

   illuminates 
  it, 
  for 
  the 
  most 
  part 
  in 
  radial 
  lines 
  up 
  to 
  the 
  region 
  

   of 
  the 
  streamers, 
  where 
  it 
  is 
  in 
  a 
  sense 
  shut 
  off, 
  thus 
  producing 
  

   the 
  effect 
  of 
  great 
  equatorial 
  extension. 
  Coronal 
  material 
  may 
  

   accumulate 
  along 
  the 
  equatorial 
  regions 
  for 
  immense 
  distances, 
  

   and 
  then 
  the 
  radiant 
  light 
  streaming 
  through 
  it 
  would 
  produce 
  

   the 
  wings 
  of 
  the 
  corona. 
  It 
  is 
  evident 
  that 
  the 
  quadrilateral 
  

   forms 
  are 
  made 
  by 
  the 
  perspective 
  thickening 
  of 
  the 
  coronal 
  

   belt 
  as 
  it 
  passes 
  round 
  the 
  side 
  of 
  the 
  sun. 
  The 
  polar 
  rays 
  are 
  

   the 
  individual 
  streamers 
  seen 
  in 
  projection. 
  

  

  The 
  reproduction 
  of 
  the 
  eclipse 
  photographs 
  is 
  necessarily 
  

   such 
  as 
  to 
  diminish 
  very 
  much 
  their 
  availability 
  as 
  objects 
  of 
  

   comparison. 
  This 
  should 
  in 
  fact 
  be 
  made 
  with 
  the 
  glass 
  nega- 
  

   tives. 
  Still 
  it 
  is 
  easy 
  to 
  infer 
  that 
  there 
  is 
  an 
  agreement 
  in 
  

   the 
  following 
  respects 
  : 
  (1) 
  as 
  to 
  the 
  general 
  inclination 
  of 
  the 
  

   corona 
  as 
  a 
  whole 
  to 
  the 
  plane 
  of 
  the 
  ecliptic 
  ; 
  (2) 
  as 
  to 
  the 
  

   general 
  distribution 
  of 
  the 
  larger 
  and 
  the 
  smaller 
  sides, 
  sup- 
  

   posing 
  that 
  the 
  nebulous 
  matter 
  is 
  supplied 
  to 
  the 
  model 
  by 
  

   the 
  imagination 
  ; 
  (3) 
  as 
  to 
  the 
  trend 
  of 
  the 
  stream 
  lines 
  

   wherever 
  they 
  are 
  seen. 
  We 
  do 
  not 
  pretend 
  to 
  show 
  all 
  the 
  

   individual 
  lines, 
  nor 
  all 
  the 
  special 
  solar 
  outbursts 
  in 
  loco, 
  nor 
  

   do 
  we 
  pretend 
  to 
  account 
  for 
  all 
  the 
  imperfections 
  of 
  the 
  pho- 
  

   tographs 
  or 
  drawings. 
  Those 
  which 
  are 
  composite, 
  or 
  which 
  

   are 
  halated, 
  or 
  which 
  are 
  inadequate, 
  must 
  take 
  their 
  chances. 
  

  

  