﻿8 
  

  

  ON 
  THE 
  DIURNAL 
  VARIATION 
  

  

  scending 
  to 
  the 
  sunrise 
  minimum, 
  when 
  the 
  observation 
  at 
  3 
  A.M. 
  showed 
  

   a 
  rise 
  of 
  temperature, 
  and 
  a 
  haze 
  is 
  noted 
  at 
  the 
  same 
  time 
  ; 
  No. 
  2 
  

   in 
  like 
  manner 
  is 
  descending 
  to 
  the 
  same 
  minimum, 
  when, 
  at 
  between 
  

   10 
  and 
  11 
  P.M., 
  an 
  irregular 
  rise 
  commences, 
  and 
  a 
  fog 
  is 
  noted, 
  

   varying 
  only 
  in 
  density, 
  until 
  late 
  in 
  the 
  morning 
  : 
  this 
  fog 
  checked 
  

   more 
  or 
  less 
  completely 
  the 
  powerful 
  radiation 
  from 
  the 
  earth, 
  which 
  

   was 
  going 
  on 
  before 
  the 
  screen 
  of 
  fog 
  was 
  interposed 
  between 
  the 
  earth 
  

   and 
  sky. 
  

  

  It 
  is 
  worthy 
  of 
  note, 
  that 
  in 
  No. 
  1, 
  at 
  the 
  observation 
  preceding 
  the 
  

   remark 
  " 
  hazy," 
  we 
  find 
  the 
  memorandum, 
  " 
  needle 
  vibrating." 
  

  

  TABLE 
  III. 
  

  

  Hour. 
  

  

  N. 
  Pole 
  W. 
  

  

  Temp. 
  

  

  Remarks. 
  

  

  Hour. 
  

  

  N. 
  Pole 
  W. 
  

  

  Temp. 
  

  

  Remarks. 
  

  

  

  Deg. 
  Min. 
  

  

  Deg. 
  

  

  

  

  Deg. 
  Min. 
  

  

  Deg. 
  

  

  

  12 
  M. 
  

  

  3 
  26.3 
  

  

  814 
  

  

  Aug. 
  31. 
  

  

  

  

  

  Sept. 
  1. 
  

  

  1 
  P.M. 
  

  

  3 
  25.4 
  

  

  S3 
  

  

  fShowercomesup, 
  

   lasts4m.;recom- 
  

  

  

  

  

  

  2 
  P.M. 
  

  

  3 
  26.5 
  

  

  841 
  

  

  ■> 
  mences 
  at 
  2h. 
  

   11m. 
  and 
  rains 
  

   ^ 
  until 
  2h. 
  27m. 
  

   C 
  Ceases 
  to 
  rain 
  for 
  

  

  

  

  

  

  2i 
  P.M. 
  

  

  3 
  10.7 
  

  

  84f 
  

  

  3 
  an 
  instant, 
  then 
  

   £ 
  recommences. 
  

  

  

  

  

  

  3 
  P.M. 
  

  

  3 
  25.S 
  

  

  82^ 
  

  

  Sun 
  out. 
  

  

  

  

  

  

  4 
  P.M. 
  

  

  3 
  23.8 
  

  

  85^ 
  

  

  Sununderacloud. 
  

  

  

  

  

  

  5| 
  P.M. 
  

  

  3 
  23.2 
  

  

  84* 
  

  

  f 
  Sun 
  under 
  a 
  cloud. 
  

   \ 
  Gust 
  to 
  N. 
  of 
  W. 
  

  

  

  

  

  

  5| 
  P.M. 
  

  

  3 
  10.3 
  

  

  79f 
  

  

  Rain 
  just 
  begun. 
  

   C 
  Heavy 
  part 
  of 
  

  

  

  

  

  

  6 
  P.M. 
  

  

  3 
  14.3 
  

  

  78§ 
  

  

  J 
  gust 
  has 
  passed. 
  

   1 
  Thunder 
  to 
  S.E. 
  

   'Needlevibrating. 
  

  

  

  

  

  

  7 
  P.M. 
  

  

  (3 
  32.0? 
  

   <3 
  36.8$ 
  

  

  773 
  

  

  No 
  rain. 
  Much 
  

   ] 
  thunder 
  and 
  

   [_ 
  lightning. 
  

   C 
  Raining 
  steadily. 
  

  

  

  

  

  

  8 
  P.M. 
  

  

  3 
  32.4 
  

  

  78f 
  

  

  < 
  Gust 
  has 
  entire- 
  

   £ 
  ly 
  passed. 
  

  

  8 
  A.M. 
  

  

  3 
  23.8 
  

  

  711 
  

  

  Clear. 
  

   C 
  Cloudy. 
  Therm. 
  

   <. 
  placed 
  in 
  com- 
  

   ^ 
  pass 
  box. 
  

  

  9 
  P.M. 
  

  

  3 
  31.7 
  

  

  77f 
  

  

  f 
  Not 
  raining. 
  

   \ 
  Cloudy. 
  

  

  9 
  A.M. 
  

  

  3 
  18.3 
  

  

  64 
  

  

  10 
  P.M. 
  

  

  3 
  32.0 
  

  

  75 
  

  

  Cloudy. 
  

  

  10 
  A.M. 
  

  

  3 
  19.1 
  

  

  65 
  

  

  C 
  Cumulus. 
  Sky 
  

   l 
  generally 
  clear. 
  

  

  11 
  P.M. 
  

  

  3 
  26.5 
  

  

  75 
  

  

  Raining 
  slightly. 
  

  

  11 
  A.M. 
  

  

  3 
  19.9 
  

  

  

  

  12 
  m. 
  

  

  3 
  26.2 
  

  

  71 
  

  

  C 
  Perfectly 
  clear. 
  

   1 
  Wind 
  N. 
  W. 
  

  

  12 
  M. 
  

  

  3 
  20.4 
  

  

  67 
  

  

  C 
  Approximate, 
  

   < 
  calculated 
  from 
  

   ( 
  that 
  at 
  12* 
  P.M. 
  

  

  