﻿46 
  Mr. 
  O. 
  Rosenheim. 
  A 
  Preliminary 
  Study 
  of 
  the 
  Energy 
  

  

  both 
  operating 
  and 
  setting.* 
  The 
  operations 
  included 
  parting, 
  recessing, 
  

   turning 
  (hand-feed), 
  screw 
  cutting, 
  hand-chasing 
  screws, 
  boring 
  (hand-feed 
  

   and 
  from 
  headstock), 
  etc. 
  Two 
  types 
  of 
  lathes 
  were 
  in 
  use 
  : 
  (1) 
  centre 
  

   lathes 
  (6", 
  7", 
  and 
  9") 
  and 
  (2) 
  Herbert 
  capstan 
  lathes 
  (No. 
  4 
  medium 
  and 
  

   No. 
  9 
  heavy). 
  The 
  latter, 
  as 
  used 
  in 
  the 
  manufacturing 
  industrial 
  shops, 
  

   were 
  supplied 
  by 
  the 
  Ministry 
  of 
  Munitions. 
  

  

  In 
  absence 
  of 
  any 
  simple 
  methods 
  for 
  the 
  actual 
  measurement 
  of 
  work 
  

   performed, 
  a 
  somewhat 
  arbitrary 
  division 
  became 
  necessary 
  into 
  light, 
  

   medium, 
  and 
  hard 
  work. 
  The 
  operations 
  of 
  parting, 
  screw-cutting, 
  or 
  

   chasing, 
  turning, 
  etc., 
  which 
  necessitated 
  merely 
  the 
  exertion 
  of 
  a 
  slight 
  

   constant 
  pressure 
  during 
  the 
  turning 
  of 
  a 
  handle, 
  were 
  classified 
  as 
  " 
  light 
  " 
  

   work. 
  Eough 
  turning, 
  boring 
  (hand-feed), 
  and 
  similar 
  operations 
  repre- 
  

   sented 
  " 
  medium 
  hard 
  " 
  work, 
  whilst 
  operations 
  involving 
  several 
  turns 
  of 
  

   the 
  capstan 
  or 
  boring 
  heavy 
  work 
  from 
  headstock, 
  etc., 
  were 
  taken 
  to 
  

   represent 
  " 
  hard 
  " 
  work. 
  The 
  " 
  work 
  " 
  experiments 
  by 
  each 
  subject 
  were 
  

   not 
  carried 
  out 
  consecutively, 
  but 
  on 
  different 
  days, 
  usually 
  in 
  the 
  afternoon. 
  

   In 
  each 
  category 
  of 
  work 
  all 
  the 
  subjects 
  performed 
  as 
  far 
  as 
  possible 
  the 
  

   same 
  operations 
  on 
  the 
  same 
  type 
  of 
  lathe. 
  For 
  the 
  final 
  calculation 
  of 
  the 
  

   energy 
  output 
  during 
  the 
  eight 
  hours' 
  working 
  period, 
  it 
  was 
  considered, 
  

   after 
  investigation 
  of 
  the 
  actual 
  conditions, 
  that 
  not 
  more 
  than 
  two 
  hours 
  

   should 
  be 
  allotted 
  to 
  hard 
  work, 
  and 
  that 
  the 
  mean 
  between 
  " 
  light 
  " 
  and 
  

   " 
  medium 
  hard 
  " 
  work 
  would 
  fairly 
  represent 
  the 
  remaining 
  six 
  working 
  

   hours. 
  

  

  (c) 
  Metabolism 
  during 
  Recreation. 
  — 
  For 
  various 
  reasons, 
  it 
  is 
  obvious 
  that 
  

   any 
  estimate 
  of 
  the 
  energy 
  expenditure 
  during 
  the 
  active 
  non-working 
  

   period 
  can 
  only 
  be 
  approximate. 
  By 
  taking 
  the 
  energy 
  expenditure 
  during 
  

   walking, 
  standing, 
  and 
  sitting 
  as 
  a 
  basis 
  of 
  calculation, 
  we 
  shall 
  probably 
  err 
  

   in 
  underestimating 
  rather 
  than 
  in 
  overestimating 
  the 
  bodily 
  activities 
  of 
  the 
  

   average 
  working 
  girl 
  during 
  recreation 
  hours. 
  As 
  a 
  result 
  of 
  personal 
  

   enquiries 
  from 
  the 
  subjects 
  of 
  this 
  study, 
  it 
  would 
  seem 
  that 
  these 
  three 
  

   forms 
  of 
  activities 
  would 
  be 
  fairly 
  apportioned 
  by 
  ascribing 
  hours 
  to 
  

   walking, 
  3£ 
  hours 
  to 
  sitting, 
  and 
  3 
  hours 
  to 
  standing. 
  In 
  all 
  cases 
  the 
  

   energy 
  expenditure 
  during 
  standing 
  was 
  estimated 
  whilst 
  the 
  subject 
  stood 
  

   in 
  an 
  easy 
  relaxed 
  position, 
  and 
  some 
  time 
  after 
  the 
  performance 
  of 
  any 
  

   active 
  work. 
  The 
  walking 
  experiments, 
  were 
  carried 
  out 
  on 
  the 
  level, 
  the 
  

   stone-paved 
  corridor 
  of 
  the 
  College 
  (80 
  m. 
  long) 
  serving 
  as 
  a 
  convenient 
  

   course, 
  necessitating 
  only 
  one 
  turning 
  movement 
  in 
  a 
  two 
  minutes' 
  walk. 
  

  

  * 
  The 
  exercises 
  were 
  arranged 
  by 
  the 
  manager 
  of 
  the 
  school, 
  Mr. 
  H. 
  G-. 
  Taylor, 
  

   Lecturer 
  on 
  Engineering, 
  King's 
  College, 
  to 
  whom 
  I 
  am 
  greatly 
  indebted 
  for 
  information 
  

   and 
  kind 
  help 
  in 
  carrying 
  out 
  this 
  investigation. 
  

  

  