﻿192 
  

  

  Surgeon- 
  Major 
  F. 
  de 
  Chaumont 
  on 
  the 
  

  

  [Jan. 
  28, 
  

  

  both 
  actually 
  and 
  relatively, 
  the 
  excess 
  being 
  0*687 
  of 
  a 
  grain 
  and 
  the 
  

   lowering 
  of 
  humidity 
  being 
  about 
  7*6 
  per 
  cent. 
  

  

  3. 
  Carbonic 
  Acid. 
  — 
  The 
  mean 
  amount 
  in 
  the 
  outer 
  air 
  was 
  0*4110 
  per 
  

   1000 
  volumes, 
  in 
  the 
  inhabited 
  air-spaces 
  0*8004, 
  or 
  a 
  mean 
  difference 
  

   (respiratory 
  impurity) 
  of 
  0*3894. 
  The 
  range 
  for 
  the 
  probable 
  error 
  of 
  

   result 
  lies 
  between 
  0*4057 
  and 
  0*3731. 
  

  

  We 
  may 
  therefore 
  say 
  that 
  ventilation 
  ceases 
  to 
  be 
  good 
  when 
  the 
  fol- 
  

   lowing 
  conditions 
  are 
  present 
  : 
  — 
  

  

  Yapour 
  in 
  the 
  air 
  exceeds 
  4*7 
  grains 
  per 
  cubic 
  foot. 
  

  

  C0 
  2 
  in 
  excess 
  over 
  outer 
  air, 
  ratio 
  reaching 
  0*4000 
  per 
  1000 
  volumes. 
  

  

  No. 
  3 
  (see 
  Table 
  No. 
  3). 
  — 
  " 
  Close 
  " 
  &c. 
  : 
  the 
  point 
  at 
  which 
  the 
  

   organic 
  matter 
  begins 
  to 
  be 
  decidedly 
  disagreeable 
  to 
  the 
  

   senses. 
  

  

  1. 
  Temperature. 
  — 
  The 
  temperature 
  in 
  this 
  series 
  was 
  more 
  near 
  the 
  

   mean 
  of 
  our 
  climate, 
  viz. 
  51°*28. 
  The 
  mean 
  in 
  the 
  inhabited 
  air-space 
  

   was 
  64°* 
  67, 
  or 
  a 
  mean 
  excess 
  of 
  12°-91. 
  

  

  2. 
  Vapour 
  and 
  Humidity. 
  — 
  The 
  vapour 
  in 
  the 
  outer 
  air 
  was 
  3*837, 
  and 
  

   in 
  the 
  inhabited 
  air-space 
  4*909, 
  a 
  mean 
  difference 
  of 
  1*072 
  grain 
  per 
  

   cubic 
  foot. 
  The 
  drying 
  of 
  the 
  air 
  amounted 
  to 
  a 
  lowering 
  of 
  the 
  humidity 
  

   by 
  11*56 
  per 
  cent. 
  

  

  3. 
  Carbonic 
  Acid. 
  — 
  The 
  carbonic 
  acid 
  in 
  the 
  outer 
  air 
  was 
  0*3705 
  per 
  

   1000 
  volumes, 
  rather 
  below 
  the 
  average. 
  In 
  the 
  inhabited 
  air-spaces 
  it 
  

   was 
  1*0027, 
  or 
  a 
  mean 
  difference 
  of 
  0*6332 
  due 
  to 
  respiratory 
  impurity, 
  

   the 
  range 
  for 
  the 
  probable 
  error 
  of 
  result 
  being 
  between 
  0*6477 
  and 
  

   0*6167. 
  

  

  We 
  may 
  therefore 
  say 
  that 
  ventilation 
  begins 
  to 
  be 
  decidedly 
  bad 
  when 
  

   the 
  following 
  conditions 
  are 
  reached 
  : 
  — 
  

   Yapour 
  reaches 
  4*9 
  grains 
  per 
  cubic 
  foot. 
  

  

  Carbonic 
  acid 
  in 
  excess 
  over 
  outer 
  air 
  to 
  the 
  amount 
  of 
  0*6000 
  per 
  

   1000 
  volumes. 
  

  

  No. 
  4 
  (see 
  Table 
  No. 
  4). 
  — 
  " 
  Yery 
  close 
  " 
  &c. 
  : 
  the 
  point 
  at 
  which 
  the 
  

   organic 
  matter 
  begins 
  to 
  be 
  offensive 
  and 
  oppressive 
  to 
  the 
  

   senses. 
  

  

  1. 
  Temperature. 
  — 
  The 
  mean 
  external 
  temperature 
  was 
  51°*28, 
  and 
  the 
  

   internal 
  65°- 
  15, 
  or 
  a 
  mean 
  difference 
  of 
  13°*87. 
  

  

  2. 
  Vapour 
  and 
  Humidity. 
  — 
  The 
  mean 
  vapour 
  in 
  the 
  outer 
  air 
  was 
  

   3*678 
  grains, 
  and 
  in 
  the 
  inhabited 
  air-spaces 
  5*078, 
  or 
  a 
  mean 
  difference 
  

   of 
  1*400 
  grain 
  per 
  cubic 
  foot. 
  This 
  corresponds 
  to 
  a 
  lowering 
  of 
  the 
  

   humidity 
  by 
  8°*58 
  per 
  cent. 
  

  

  3. 
  Carbonic 
  Acid. 
  — 
  The 
  mean 
  amount 
  in 
  the 
  outer 
  air 
  was 
  0*3903 
  per 
  

   1000 
  volumes, 
  pretty 
  near 
  the 
  usual 
  average. 
  In 
  the 
  inhabited 
  air-spaces 
  

   it 
  was 
  1*2335, 
  or 
  a 
  mean 
  difference 
  due 
  to 
  respiratory 
  impurity 
  of 
  

  

  