﻿306 
  PRACTICAL 
  RULE 
  FOR 
  CALCULATING 
  

  

  h. 
  m. 
  

   At. 
  6 
  0-3 
  

   p 
  — 
  w= 
  — 
  5-34, 
  q 
  — 
  v 
  = 
  + 
  0-94, 
  u 
  = 
  + 
  2-33, 
  v 
  = 
  + 
  8-64 
  

  

  q 
  — 
  v 
  + 
  0-94 
  

  

  y 
  = 
  - 
  K 
  * 
  A 
  = 
  — 
  -176 
  P 
  = 
  280°-0 
  

  

  p 
  — 
  u 
  — 
  5-34 
  

  

  « 
  + 
  2 
  ' 
  33 
  

  

  — 
  = 
  , 
  a 
  ft/< 
  = 
  + 
  "269 
  Q 
  = 
  15°-1 
  

  

  V 
  = 
  Q 
  — 
  P= 
  95°-l 
  

  

  Changing 
  the 
  Greenwich 
  mean 
  times 
  into 
  Philadelphia 
  mean 
  times, 
  

   we 
  have, 
  

  

  h. 
  m. 
  

   Beginning, 
  59-6 
  

  

  Greatest 
  obscuration, 
  2 
  21-7 
  

   End, 
  3 
  37-8 
  

  

  The 
  first 
  part 
  of 
  the 
  calculation, 
  by 
  note 
  2d 
  to 
  the 
  rule, 
  is 
  the 
  same 
  

   as 
  the 
  preceding, 
  except 
  that 
  /"need 
  not 
  be 
  found. 
  The 
  subsequent 
  

   part, 
  after 
  the 
  time 
  of 
  greatest 
  obscuration 
  is 
  obtained, 
  is 
  as 
  follows 
  : 
  — 
  

  

  h. 
  m. 
  

   T'= 
  7 
  22-4 
  

  

  p 
  = 
  + 
  4-57, 
  q= 
  + 
  7-58, 
  H 
  = 
  + 
  38°-2 
  

  

  u 
  =» 
  4- 
  4-75, 
  C 
  =» 
  + 
  6-03, 
  c 
  = 
  — 
  2-23, 
  v— 
  + 
  8-16 
  

   ;; 
  — 
  u 
  = 
  — 
  0-18 
  sq. 
  0-03 
  

  

  q 
  — 
  v 
  = 
  — 
  0-58 
  sq. 
  0-34 
  

  

  m 
  = 
  0.61 
  sq. 
  0.37 
  

  

  6(k 
  — 
  m) 
  4-82 
  + 
  6 
  ~ 
  nm 
  . 
  . 
  ,. 
  , 
  

  

  ~~ 
  '• 
  — 
  == 
  — 
  2^70 
  — 
  = 
  = 
  digits 
  eclipsed. 
  

  

  k 
  = 
  5-43 
  sq. 
  29-48 
  

  

  m 
  sq. 
  0-37 
  

  

  h 
  = 
  5-40 
  sq. 
  29-11 
  

  

  m. 
  h. 
  m. 
  

   4-00 
  : 
  5-40 
  : 
  : 
  60 
  : 
  1 
  21-0 
  

   h. 
  m. 
  h. 
  m. 
  h. 
  m. 
  

  

  7 
  22-4 
  — 
  1 
  21-0 
  = 
  6 
  1-4 
  = 
  approx. 
  time 
  of 
  begin. 
  

   7 
  22-4 
  + 
  1 
  21-0 
  »= 
  8 
  43-4 
  = 
  approx. 
  time 
  of 
  end. 
  

  

  h. 
  m. 
  

   T' 
  = 
  6 
  1-4 
  

   p 
  = 
  — 
  2-91, 
  7 
  = 
  + 
  9-55, 
  H 
  = 
  17°-9 
  

   u 
  = 
  + 
  2-36, 
  C 
  = 
  4- 
  7-30, 
  c 
  = 
  — 
  2-70, 
  v 
  — 
  + 
  8-63 
  

  

  

  