﻿Exercise 
  and 
  Humid 
  Heat 
  upon 
  Pulse 
  Rate, 
  etc. 
  

  

  123 
  

  

  the 
  experimental 
  error, 
  varying 
  between 
  15 
  and 
  3 
  - 
  l. 
  In 
  three 
  experiments 
  

   there 
  was 
  an 
  increase, 
  but 
  within 
  the 
  error 
  limit, 
  and 
  an 
  actual 
  but 
  small 
  

   decrease 
  was 
  observed 
  in 
  two 
  experiments. 
  The 
  increase 
  in 
  the 
  blood 
  solids 
  

   in 
  the 
  different 
  experiments 
  was 
  not 
  proportionate 
  to 
  the 
  loss 
  in 
  body 
  weight. 
  

   In 
  the 
  detailed 
  Table 
  a 
  column 
  is 
  given 
  indicating 
  the 
  loss 
  of 
  water 
  from 
  the 
  

   blood, 
  which 
  would 
  correspond 
  to 
  the 
  increase 
  in 
  the 
  solids 
  actually 
  observed. 
  

   Considering 
  the 
  small 
  actual 
  difference 
  in 
  the 
  weighings, 
  these 
  calculations 
  

   are 
  only 
  very 
  approximate, 
  and 
  only 
  the 
  one 
  conclusion 
  is 
  justified 
  — 
  that 
  

   there 
  is 
  a 
  tendency 
  to 
  increased 
  blood 
  solids 
  brought 
  about 
  by 
  copious 
  

   sweating. 
  

  

  The 
  refractive 
  index 
  of 
  the 
  serum 
  was 
  measured 
  before 
  and 
  after 
  copious 
  

   perspiration. 
  The 
  blood 
  was 
  collected 
  from 
  the 
  ear 
  by 
  means 
  of 
  a 
  Wright's 
  

   tube, 
  allowed 
  to 
  clot 
  and 
  centrifugalised, 
  and 
  the 
  serum 
  examined 
  by 
  means 
  

   of 
  a 
  Zeiss-Abbe 
  refractometer. 
  In 
  a 
  few 
  instances 
  serum 
  of 
  blood 
  obtained 
  

   from 
  the 
  ear 
  and 
  from 
  the 
  finger 
  were 
  compared 
  and 
  yielded 
  identical 
  results. 
  

   In 
  every 
  case 
  the 
  refractive 
  index 
  of 
  the 
  serum 
  was 
  higher 
  after 
  profuse 
  

   sweating, 
  whether 
  brought 
  about 
  by 
  exercise 
  or 
  merely 
  by 
  exposure 
  to 
  

   excessive 
  moist 
  heat 
  as 
  shown 
  in 
  Table 
  VII. 
  

  

  In 
  the 
  Table 
  a 
  column 
  of 
  figures 
  is 
  given 
  which 
  represents 
  the 
  percentage 
  

   of 
  water 
  lost 
  from 
  the 
  blood, 
  calculated 
  from 
  the 
  increase 
  in 
  the 
  refractive 
  

   index. 
  The 
  figures 
  were 
  arrived 
  at 
  in 
  the 
  following 
  manner 
  : 
  A 
  series 
  of 
  

   weighed 
  quantities 
  of 
  goat's 
  blood 
  was 
  allowed 
  to 
  evaporate 
  slowly 
  in 
  a 
  

   desiccator 
  over 
  sulphuric 
  acid, 
  and 
  the 
  increase 
  in 
  the 
  refractive 
  index 
  of 
  the 
  

   serum 
  was 
  then 
  plotted 
  against 
  the 
  corresponding 
  loss 
  of 
  water 
  from 
  the 
  

   blood, 
  and 
  a 
  curve 
  smoothed 
  through 
  the 
  points. 
  From 
  this 
  curve 
  the 
  

   percentage 
  of 
  loss 
  of 
  water 
  from 
  the 
  blood 
  corresponding 
  to 
  the 
  increase 
  in 
  

   the 
  refractive 
  index 
  of 
  the 
  serum 
  could 
  be 
  obtained. 
  

  

  On 
  comparing 
  the 
  total 
  loss 
  in 
  body 
  weight 
  with 
  the 
  calculated 
  loss 
  of 
  

   water 
  from 
  the 
  blood, 
  based 
  on 
  the 
  refractive 
  index 
  of 
  the 
  serum, 
  it 
  is 
  clear 
  

   that 
  the 
  greater 
  part 
  of 
  the 
  sweat 
  must 
  be 
  derived 
  from 
  other 
  sources 
  than 
  

   the 
  blood, 
  although 
  the 
  experiments 
  show 
  that 
  at 
  least 
  part 
  of 
  the 
  fluid 
  lost 
  

   is 
  derived 
  from 
  the 
  blood 
  plasma. 
  

  

  It 
  will 
  be 
  observed 
  also 
  from 
  the 
  Table 
  that 
  the 
  quantity 
  of 
  water 
  lost 
  

   from 
  the 
  blood, 
  as 
  calculated 
  from 
  the 
  refractive 
  index, 
  and 
  that 
  estimated 
  

   from 
  the 
  increase 
  in 
  the 
  total 
  solids 
  of 
  the 
  blood, 
  do 
  not 
  agree, 
  but, 
  as 
  

   pointed 
  out 
  previously, 
  the 
  errors 
  in 
  estimating 
  the 
  total 
  solids 
  were 
  too 
  

   great 
  to 
  consider 
  this 
  method 
  more 
  than 
  a 
  qualitative 
  one. 
  

  

  The 
  estimation 
  of 
  the 
  refractive 
  index 
  gave 
  such 
  constant 
  results 
  that 
  one 
  

   must 
  conclude 
  that 
  a 
  definite 
  concentration 
  of 
  the 
  blood 
  does 
  take 
  place 
  as 
  

   the 
  result 
  of 
  copious 
  sweating. 
  The 
  percentages, 
  however, 
  seem 
  rather 
  high, 
  

  

  vol. 
  xui. 
  — 
  b. 
  K 
  

  

  