﻿436 
  

  

  ON 
  THE 
  RELATIVE 
  HORIZONTAL 
  INTENSITIES 
  

  

  on 
  the 
  glass 
  cover 
  of 
  the 
  box 
  a 
  zero 
  line 
  and 
  graduations, 
  similar 
  to 
  

   those 
  on 
  the 
  scale 
  at 
  the 
  bottom 
  of 
  the 
  box. 
  

  

  Some 
  of 
  the 
  results 
  were 
  carried 
  from 
  semi-arcs 
  of 
  twenty-five 
  to 
  

   three 
  degrees, 
  but 
  the 
  observations 
  below 
  the 
  semi-arcs 
  of 
  five 
  degrees 
  

   are 
  omitted. 
  The 
  series 
  thus 
  requires 
  no 
  correction 
  for 
  arc, 
  to 
  obtain 
  

   relative 
  results. 
  The 
  observations 
  made 
  below 
  five 
  degrees 
  were 
  not 
  

   as 
  accordant 
  as 
  those 
  above; 
  they 
  were, 
  however, 
  few 
  in 
  number. 
  

  

  The 
  experiments 
  just 
  detailed 
  occupied 
  almost 
  the 
  entire 
  interval 
  

   between 
  10^ 
  A. 
  M. 
  on 
  the 
  25th, 
  and 
  12^ 
  A. 
  M. 
  on 
  the 
  26th 
  of 
  Au- 
  

   gust 
  1834; 
  they 
  are, 
  therefore, 
  affected 
  by 
  the 
  diurnal 
  variation. 
  

   Needle 
  No. 
  1 
  was 
  vibrated 
  at 
  intervals 
  to 
  determine 
  the 
  amount 
  of 
  

   this 
  correction 
  ; 
  but 
  the 
  nature 
  of 
  the 
  results 
  did 
  not 
  warrant 
  the 
  use 
  

   of 
  any 
  correction 
  derived 
  from 
  this 
  source. 
  

  

  The 
  following 
  table 
  contains 
  the 
  record 
  of 
  the 
  observations 
  just 
  re- 
  

   ferred 
  to. 
  The 
  several 
  columns 
  contain, 
  first, 
  the 
  number 
  of 
  the 
  ex- 
  

   periment, 
  for 
  reference; 
  second, 
  the 
  designation 
  of 
  the 
  needle; 
  third, 
  

   fourth 
  and 
  fifth, 
  the 
  times 
  of 
  beginning 
  and 
  ending 
  the 
  oscillations; 
  

   sixth, 
  the 
  temperatures 
  at 
  the 
  beginning 
  and 
  end 
  ; 
  seventh, 
  the 
  num- 
  

   ber 
  of 
  oscillations 
  between 
  the 
  semi-arcs 
  of 
  twenty 
  and 
  of 
  five 
  degrees 
  ; 
  

   eighth, 
  the 
  mean 
  temperature; 
  ninth, 
  the 
  time 
  of 
  ten 
  vibrations. 
  

  

  TABLE 
  No. 
  I. 
  

  

  Observations 
  for 
  Correction 
  for 
  Temperature 
  of 
  Needles 
  1, 
  2 
  and 
  3. 
  

  

  "S 
  

  

  g 
  

  

  <u 
  

   H 
  

  

  '— 
  

   o 
  

  

  d 
  

   Z 
  

  

  a 
  

  

  <o 
  

  

  Z 
  

  

  o 
  

  

  6 
  

  

  iz; 
  

  

  Times 
  

  

  of 
  

  

  Beginning 
  and 
  End. 
  

  

  Temperatures 
  

  

  at 
  Beginning 
  

  

  and 
  End. 
  

  

  03 
  

  

  c 
  

   c 
  

  

  > 
  

  

  o 
  

   6 
  

  

  0) 
  - 
  

  

  ° 
  a 
  

  

  Observers' 
  Names, 
  &c. 
  

  

  Hours. 
  

  

  Mins. 
  

  

  Sees. 
  

  

  Fah.° 
  

  

  Fah.° 
  

  

  Sees. 
  

  

  1. 
  

  

  1. 
  

  

  P.M. 
  

  

  12 
  

   1 
  

  

  38 
  

   08 
  

  

  44.0 
  

   08.6 
  

  

  36 
  

   32 
  

  

  390 
  

  

  33.6 
  

  

  45.25 
  

  

  August 
  25th, 
  1834. 
  

   Bache. 
  

  

  2. 
  

  

  i> 
  

  

  P.M. 
  

  

  4 
  

  

  30 
  

   56 
  

  

  19.2 
  

   00.2 
  

  

  35£ 
  

   35A 
  

  

  340 
  

  

  35.7 
  

  

  45.32 
  

  

  Bache 
  and 
  Courtenay. 
  

  

  3. 
  

  

  n 
  

  

  P.M. 
  

  

  8 
  

  

  04 
  

   31 
  

  

  00.0 
  

   40.5 
  

  

  98 
  

   100 
  

  

  356 
  

  

  99.1 
  

  

  46.64 
  

  

  Bache 
  and 
  Courtenay. 
  

  

  4. 
  

  

  5. 
  

  

  it 
  

  

  P.M. 
  

   A.M. 
  

  

  11 
  

  

  12 
  

  

  51 
  

   19 
  

  

  16.4 
  

  

  20.8 
  

  

  98 
  

   98 
  

  

  362 
  

  

  98 
  

  

  46.53 
  

  

  Bache. 
  (August 
  26.) 
  

  

  2. 
  

  

  P.M. 
  

  

  1 
  

   2 
  

  

  44 
  

   09 
  

  

  35.8 
  

   14.6 
  

  

  32 
  

   32| 
  

  

  340 
  

  

  32.2 
  

  

  43.50 
  

  

  Bache. 
  

  

  6. 
  

   7. 
  

  

  3. 
  

  

  P.M. 
  

  

  10 
  

  

  11 
  

  

  42 
  

   14 
  

  

  47.8 
  

   25.8 
  

  

  98 
  

   102 
  

  

  424 
  

  

  99.3 
  

  

  44.77 
  

  

  Bache 
  and 
  Courtenay. 
  

  

  P.M. 
  

  

  2 
  

  

  36 
  

   50 
  

  

  45.0 
  

   24.6 
  

  

  35 
  

   36 
  

  

  170 
  

  

  35.3 
  

  

  48.21 
  

  

  Bache. 
  

  

  8. 
  

  

  ci 
  

  

  P.M. 
  

  

  9 
  

   10 
  

  

  51 
  

  

  06 
  

  

  22.2 
  

   16.2 
  

  

  102 
  

   102| 
  

  

  182 
  

  

  102.2 
  

  

  49.12 
  

  

  Bache 
  and 
  Courtenay. 
  

  

  