tch you will find 48.7 and 64.7 opposite each other,
and as 48.7 is in the Lat. column only when you read from the bottom,
the course is S 53 deg. E. The real difference of Lat. under this course is
opposite 62 in the distance column. Hence the distance to be sailed is
62 miles.

If distances are too great, divide meridional difference of Lat., real
difference of Latitude and difference of Longitude by 10 or any other
number to bring them within the scope of the distances in Table 2. When
distance to be sailed is found, it must be multiplied by the same
number. For instance, if the difference of Lat., difference of Lo.,
etc., are divided by 10 to bring them in the scope of Table 2, and with
these figures 219 is the distance found, the real distance would be 10
times 219 or 2190.

Now let us work out the same problem by logarithms. This will acquaint
us with two new Tables, i.e., Tables 42 and 44. Put this in your
Note-Book:

Lat. in 40 deg. 28' N Mer. pts. 2644.2 Lo. in 73 deg. 50'
Lat. sought 39 51 Mer. pts. 2596.0 Lo. sought 72 45
--------- ------ -------
Real diff. 0 deg. 37' 48.2 1 deg. 05'
60
--
60
5
--
(Table 42) log (+ 10) 65 = 11.81291
Log 48.2 = 1.68305
--------
Log tan TC (Table 44) 10.12986
TC = S 53 deg. 26' E

Log sec TC (53 deg. 26') = 10.22493
Log real diff. Lat. = 1.56820 +
--------
11.79313
- 10.
--------
1.79313

Distance (Table 42) = 62.11 miles

Find algebraically the re