﻿180 
  Dr. 
  A. 
  D. 
  Waller. 
  The 
  Physiological 
  Cost 
  of 
  Muscular 
  

  

  As 
  goods 
  come 
  in 
  he 
  is 
  told 
  off 
  in 
  gangs 
  for 
  piece-work, 
  which 
  brings 
  him 
  

   supplementary 
  pay 
  as 
  his 
  surplus. 
  He 
  wants 
  to 
  earn 
  this 
  surplus, 
  and 
  each 
  

   workman 
  does 
  so 
  under 
  the 
  automatic 
  supervision 
  of 
  his 
  mates 
  in 
  the 
  gang, 
  

   who 
  are 
  earning 
  money 
  in 
  common 
  ; 
  therefore 
  he 
  is 
  working 
  at 
  full 
  pressure, 
  

   and 
  the 
  expired 
  air 
  collected 
  from 
  him 
  at 
  the 
  end 
  of 
  each 
  hour 
  affords 
  a 
  fair 
  

   sample 
  of 
  the 
  level 
  of 
  C0 
  2 
  expenditure 
  at 
  which 
  he 
  is 
  working. 
  This 
  

   expenditure 
  is 
  the 
  important 
  fact 
  to 
  ascertain 
  ; 
  the 
  result 
  in 
  cubic 
  centimetres 
  

   per 
  second 
  can 
  afterwards 
  be 
  translated 
  into 
  calories 
  per 
  hour, 
  and 
  in 
  this 
  

   translation 
  there 
  is 
  perhaps 
  room 
  for 
  difference 
  of 
  opinion 
  among 
  different 
  

   physiologists. 
  I 
  am 
  accustomed 
  for 
  the 
  mental 
  arithmetic 
  of 
  the 
  conversion 
  

   to 
  think 
  of 
  1 
  c.c. 
  per 
  second 
  CO2 
  as 
  representing 
  20 
  cals. 
  per 
  hour 
  ; 
  but 
  in 
  

   case 
  any 
  other 
  observer 
  should 
  be 
  of 
  a 
  different 
  opinion, 
  and 
  prefer 
  to 
  reckon 
  

   from 
  another 
  respiratory 
  quotient, 
  I 
  have 
  given 
  in 
  the 
  last 
  column 
  of 
  Table 
  VII 
  

   Kalories 
  per 
  hour 
  that 
  correspond 
  with 
  different 
  respiratory 
  quotients. 
  The 
  

   further 
  conversion 
  of 
  calories 
  per 
  hour 
  per 
  individual 
  into 
  calories 
  per 
  hour 
  

   per 
  square 
  metre 
  is, 
  of 
  course, 
  readily 
  accomplished 
  by 
  taking 
  out 
  from 
  Tables 
  

   (e.g., 
  that 
  of 
  Du 
  Bois*) 
  the 
  surface 
  values 
  corresponding 
  to 
  the 
  weight 
  and 
  

   height 
  of 
  the 
  individual 
  in 
  question. 
  Thus, 
  e.g., 
  in 
  the 
  cases 
  of 
  Labourers 
  

   No. 
  1 
  and 
  No. 
  2 
  :— 
  

  

  Labourer. 
  

  

  

  Net 
  0O 
  2 
  per 
  

   sec. 
  

  

  Net 
  Kals 
  

   per 
  hour. 
  

  

  Surface 
  in 
  

   sq. 
  metres. 
  

  

  Net 
  Kals 
  per 
  hour 
  

   per 
  sq. 
  metre. 
  

  

  No. 
  1 
  

  

  Time-work 
  

  

  12 
  -4 
  

  

  248 
  

  

  1 
  -95 
  

  

  127 
  -2 
  

  

  No. 
  2 
  

  

  Time-work 
  

  

  12 
  3 
  

  

  246 
  

  

  2 
  -00 
  

  

  123 
  -0 
  

  

  

  Piece-work 
  

  

  21 
  

  

  420 
  

  

  

  210 
  -0 
  

  

  I 
  do 
  not 
  like 
  to 
  estimate 
  a 
  day's 
  work 
  by 
  taking 
  the 
  hourly 
  estimate 
  

   multiplied 
  by 
  hours 
  of 
  work. 
  I 
  think 
  it 
  preferable 
  to 
  plot 
  the 
  C0 
  2 
  ordinate 
  

   of 
  the 
  whole 
  day 
  and 
  to 
  estimate 
  the 
  day's 
  work 
  from 
  the 
  area 
  representing 
  

   its 
  net 
  cost 
  in 
  cubic 
  centimetres 
  of 
  CO2 
  or 
  in 
  Kalories 
  (i.e., 
  cubic 
  centimetres 
  

   of 
  CO2 
  x 
  20). 
  The 
  hourly 
  figures 
  given 
  above 
  have 
  been 
  averaged 
  from 
  the 
  

   three 
  last 
  hours 
  of 
  work, 
  omitting 
  the 
  first 
  reading 
  as 
  being 
  possibly 
  too 
  low. 
  

   Estimation 
  of 
  the 
  area 
  for 
  the 
  whole 
  day 
  includes, 
  of 
  course, 
  the 
  first 
  reading 
  

   and 
  the 
  hourly 
  estimate 
  obtained 
  by 
  dividing 
  the 
  day's 
  value 
  by 
  the 
  number 
  

   of 
  hours 
  of 
  work 
  comes 
  out 
  lower 
  than 
  the 
  hourly 
  figures 
  averaged 
  from 
  the 
  

   last 
  three 
  hours. 
  In 
  the 
  case 
  of 
  Labourer 
  No. 
  2 
  the 
  net 
  cost 
  of 
  his 
  six 
  days' 
  

   work 
  calculated 
  by 
  area 
  comes 
  out 
  as 
  follows 
  : 
  — 
  

  

  * 
  Du 
  Bois 
  and 
  Du 
  Bois, 
  " 
  Tenth 
  Paper 
  on 
  Clinical 
  Calorinietry," 
  ' 
  Archives 
  of 
  

   International 
  Medicine,' 
  vol. 
  15, 
  Part 
  II 
  (May 
  15, 
  1915). 
  (It 
  is 
  stated 
  in 
  this 
  paper 
  that 
  

   Meet's 
  formula 
  12 
  - 
  313 
  W^xs 
  more 
  correctly 
  stated 
  as 
  10 
  - 
  5 
  W 
  2 
  / 
  3 
  . 
  This 
  is 
  the 
  value 
  I 
  

   found 
  by 
  direct 
  observation, 
  ' 
  Introduction 
  to 
  Human 
  Physiology,' 
  1st 
  edition.) 
  

  

  