﻿104 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  As 
  a 
  temporary 
  makeshift 
  to 
  enable 
  us 
  to 
  see 
  our 
  plates 
  as 
  

   solids 
  we 
  will 
  use 
  the 
  ordinary 
  Holmes 
  stereoscope 
  in 
  one 
  of 
  the 
  

   following 
  ways. 
  

  

  Let 
  the 
  observer 
  seat 
  himself 
  before 
  a 
  table 
  arranged 
  to 
  let 
  a 
  good 
  

   light 
  reach 
  the 
  page 
  from 
  the 
  left 
  side. 
  In 
  front 
  and 
  about 
  ten 
  inches 
  

   back 
  from 
  the 
  edge 
  of 
  the 
  table 
  place 
  two 
  or 
  three 
  moderately 
  

   heavy 
  books. 
  Slide 
  the 
  transverse 
  card 
  carrier 
  off 
  the 
  end 
  of 
  the 
  

   rail 
  of 
  the 
  stereoscope 
  and 
  place 
  this 
  end 
  against 
  the 
  lower 
  edge 
  of 
  

   the 
  bottom 
  volume. 
  By 
  now 
  placing 
  the 
  forehead 
  against 
  the 
  hood 
  

   and 
  using 
  a 
  gentle 
  pressure 
  it 
  is 
  easy 
  to 
  hold 
  the 
  instru- 
  

   ment 
  at 
  an 
  angle 
  of 
  about 
  forty-five 
  degrees 
  and 
  at 
  the 
  same 
  time 
  

   look 
  through 
  the 
  lenses. 
  Both 
  hands 
  are 
  free 
  to 
  bring 
  any 
  stere- 
  

   ogram 
  into 
  proper 
  position 
  and 
  focus. 
  The 
  line 
  separating 
  the 
  

   two 
  views 
  must 
  be 
  kept 
  near 
  the 
  center 
  of 
  the 
  rail 
  and 
  the 
  lower 
  

   edge 
  of 
  the 
  stereogram 
  kept 
  parallel 
  with 
  the 
  horizontal 
  edges 
  oi 
  

   the 
  lenses. 
  

  

  This 
  end 
  may 
  also 
  be 
  attained 
  by 
  placing 
  the 
  stereogram 
  with 
  its 
  

   lower 
  edge 
  close 
  to 
  the 
  edge 
  of 
  the 
  table 
  and 
  holding 
  it 
  as 
  nearly 
  

   flat 
  as 
  possible 
  with 
  proper 
  weights. 
  Then 
  hold 
  the 
  rail 
  of 
  the 
  

   stereoscope 
  vertically 
  against 
  the 
  edge 
  of 
  the 
  table 
  and 
  move 
  up 
  

   or 
  down 
  to 
  focus. 
  

  

  For 
  a 
  quickly 
  made 
  but 
  more 
  permanent 
  device, 
  procure 
  two 
  

   pieces 
  of 
  board, 
  one 
  10 
  inches 
  x 
  12 
  inches 
  x 
  £ 
  inch 
  and 
  the 
  other 
  

   2 
  inches 
  x 
  1 
  inch 
  x 
  J 
  inch. 
  Fasten 
  the 
  smaller 
  piece 
  under 
  the 
  

   middle 
  of 
  one 
  of 
  the 
  10 
  inch 
  edges, 
  keeping 
  the 
  two 
  £ 
  inch 
  faces 
  

   flush 
  with 
  each 
  other. 
  A 
  simple 
  clamp 
  will 
  hold 
  the 
  rail 
  of 
  the 
  

   stereoscope 
  against 
  this 
  if 
  inch 
  face. 
  Two 
  or 
  more 
  elastic 
  bands 
  

   around 
  the 
  board 
  will 
  hold 
  the 
  volume 
  to 
  the 
  stage 
  and 
  both" 
  

   hands 
  may 
  be 
  left 
  free 
  for 
  other 
  work. 
  

  

  Still 
  more 
  desirable 
  would 
  be 
  a 
  large 
  inclined 
  stage 
  with 
  spring 
  

   clips 
  and 
  a 
  stereoscope 
  body 
  that 
  could 
  be 
  focused 
  by 
  means 
  of 
  

   a 
  rack 
  and 
  pinion 
  as 
  in 
  a 
  binocular 
  microscope. 
  A 
  cheap 
  and 
  

   convenient 
  form 
  could 
  be 
  modified 
  after 
  Brewsters 
  " 
  box 
  " 
  stereo- 
  

   scope 
  in 
  which 
  the 
  loaded 
  base 
  of 
  the 
  instrument 
  should 
  rest 
  di- 
  

   rectly 
  on 
  the 
  printed 
  page. 
  

  

  If 
  the 
  reader 
  will 
  seek 
  through 
  one 
  or 
  another 
  of 
  the 
  

   means 
  here 
  suggested 
  to 
  view 
  these 
  stereograms 
  serially 
  and 
  in 
  

  

  