﻿148 
  

  

  Mr. 
  A. 
  H. 
  Garrod 
  on 
  the 
  

  

  brass 
  work 
  which 
  is 
  fastened 
  to 
  the 
  spring 
  that 
  presses 
  on 
  the 
  pulse, 
  to 
  

   the 
  end 
  of 
  which 
  a 
  small 
  wire 
  loop 
  is 
  soldered. 
  In 
  addition, 
  a 
  small 
  piece 
  

   of 
  wood 
  is 
  screwed 
  into 
  the 
  nearer 
  of 
  the 
  two 
  holes 
  by 
  which 
  the 
  watch- 
  

   work 
  was 
  fixed, 
  in 
  such 
  a 
  way 
  that 
  it 
  can 
  be 
  made 
  to 
  revolve 
  with 
  diffi- 
  

   culty. 
  The 
  two 
  instruments 
  are 
  fastened 
  together 
  by 
  means 
  of 
  a 
  screw 
  

   and 
  nut 
  in 
  the 
  foot-sphygmograph, 
  which 
  bind 
  a 
  brass 
  plate 
  in 
  that 
  for 
  

   the 
  wrist. 
  This 
  screw 
  is 
  fixed 
  on 
  a 
  plate 
  of 
  brass 
  which 
  is 
  attached 
  to 
  

   the 
  end 
  of 
  the 
  instrument 
  furthest 
  from 
  the 
  watchwork 
  in 
  the 
  manner 
  

   shown 
  in 
  the 
  figure. 
  The 
  brass 
  plate 
  in 
  the 
  other 
  sphygmograph, 
  which 
  

   it 
  binds, 
  is 
  fixed 
  on 
  the 
  side 
  of 
  the 
  body 
  of 
  the 
  instrument 
  close 
  to 
  the 
  

   arbor 
  of 
  the 
  lever. 
  The 
  exact 
  position 
  of 
  these 
  additional 
  pieces 
  of 
  brass- 
  

   work 
  has 
  to 
  be 
  determined 
  by 
  the 
  direction 
  that 
  a 
  silk 
  cord 
  takes 
  when, 
  

   fixed 
  at 
  one 
  end 
  to 
  the 
  arbor-end 
  of 
  the 
  inverted 
  lever 
  mentioned 
  above, 
  

   it 
  is 
  threaded 
  through 
  the 
  loop 
  on 
  the 
  tip 
  of 
  the 
  spring 
  of 
  the 
  wrist- 
  

   sphygmograph. 
  This 
  cord 
  has 
  to 
  be 
  parallel 
  to 
  the 
  sides 
  of 
  the 
  ankle- 
  

   sphygmograph, 
  when 
  the 
  two 
  instruments 
  are 
  fastened 
  together 
  with 
  the 
  

   nut 
  at 
  right 
  angles 
  to 
  one 
  another. 
  

  

  On 
  commencing 
  to 
  take 
  a 
  double 
  trace, 
  the 
  nut 
  is 
  unscrewed, 
  and 
  the 
  

   two 
  instruments 
  are 
  separated 
  from 
  one 
  another. 
  The 
  wrist- 
  sphygmo- 
  

   graph 
  is 
  then 
  bound, 
  as 
  usual, 
  on 
  the 
  right 
  arm. 
  The 
  silk 
  cord 
  attached 
  

   to 
  the 
  arbor-end 
  of 
  the 
  wrist-pulse 
  lever 
  (the 
  upper 
  one 
  in 
  the 
  ankle- 
  

   sphygmograph) 
  is 
  then 
  threaded 
  through 
  the 
  loop 
  at 
  the 
  tip 
  of 
  the 
  wrist- 
  

   spring, 
  and 
  the 
  binding-screw 
  to 
  fix 
  the 
  two 
  instruments 
  is 
  passed 
  into 
  

   the 
  hole 
  in 
  the 
  plate 
  of 
  the 
  wrist- 
  sphygmograph 
  made 
  to 
  receive 
  it; 
  

   after 
  which, 
  the 
  nut 
  being 
  screwed 
  fast 
  down, 
  the 
  two 
  sphygmographs 
  

   form 
  a 
  single 
  mass. 
  The 
  silk 
  cord 
  is 
  then 
  carried 
  round 
  the 
  piece 
  of 
  

   wood 
  at 
  the 
  watchwork 
  end 
  of 
  the 
  wrist-sphygmograph, 
  and, 
  after 
  being 
  

   slightly 
  tightened, 
  is 
  fixed 
  in 
  a 
  groove 
  on 
  its 
  side. 
  The 
  whole 
  is 
  now 
  

   ready 
  for 
  commencing 
  the 
  trace. 
  To 
  do 
  this 
  the 
  ankle 
  instrument 
  (with 
  

   that 
  for 
  the 
  wrist 
  attached 
  to 
  it 
  and 
  to 
  the 
  arm) 
  is 
  placed 
  over 
  the 
  left 
  

   foot, 
  which 
  has 
  to 
  rest 
  on 
  the 
  right 
  knee, 
  parallel 
  to 
  the 
  direction 
  of 
  the 
  

   leg, 
  with 
  the 
  watchwork 
  towards 
  the 
  body. 
  The 
  recording-paper 
  is 
  placed 
  

   in 
  position 
  ; 
  the 
  silk 
  thread 
  is 
  tightened, 
  by 
  slightly 
  turning 
  the 
  wooden 
  

   peg 
  to 
  which 
  it 
  is 
  fixed, 
  and 
  the 
  wrist-lever 
  is 
  made 
  to 
  pulsate 
  by 
  it 
  

   towards 
  the 
  upper 
  part 
  of 
  the 
  recording-paper. 
  The 
  ankle 
  -sphygmo- 
  

   graph, 
  held 
  by 
  its 
  watchwork 
  end 
  in 
  the 
  left 
  hand, 
  and 
  attached 
  at 
  the 
  

   other 
  extremity 
  to 
  the 
  right 
  wrist, 
  is 
  then 
  pressed 
  down 
  on 
  the 
  inside 
  of 
  

   the 
  left 
  foot 
  (which 
  rests 
  on 
  the 
  right 
  knee), 
  in 
  such 
  a 
  way 
  that 
  its 
  pulse- 
  

   pad 
  compresses 
  the 
  posterior 
  tibial 
  artery 
  where 
  its 
  pulsation 
  is 
  most 
  

   manifest. 
  The 
  lever 
  is 
  made 
  to 
  record 
  on 
  the 
  lower 
  part 
  of 
  the 
  smoked 
  

   paper, 
  below 
  the 
  one 
  connected 
  with 
  the 
  wrist. 
  When 
  both 
  levers 
  are 
  

   found 
  to 
  be 
  working 
  freely, 
  the 
  recording-paper 
  is 
  set 
  moving 
  by 
  libera- 
  

   ting 
  the 
  watchwork-catch 
  with 
  the 
  left 
  thumb, 
  which 
  is 
  close 
  to 
  it. 
  The 
  

   respiration 
  must 
  be 
  checked 
  during 
  the 
  time 
  the 
  recording-paper 
  is 
  

   moving, 
  to 
  prevent 
  irregularities 
  in 
  the 
  trace. 
  

  

  