| Dev. | Var. | New | Old
---------+------+-------------+--------+--------+-------+---------
N x E | NW | 1/2 pt. | 5 deg. E | 10 deg. W | 12 deg. | N 12 deg. E
S 67 deg. E | S | 1 pt. | 3 deg. W | 5 deg. E | 104 deg. | S 76 deg. E
E x N | SE | 1/2 pt. | 5 deg. W | 10 deg. E | 78 deg. | N 78 deg. E
W x N | NW | 1-1/2 pts. | 1 deg. E | 15 deg. E | 280 deg. | N 80 deg. W
---------+------+-------------+--------+--------+-------+---------

Assign for Night Work the following arts. in Bowditch:
36-8-10-13-14-15-16-17-18-19-20-21-22-23-24.

WEDNESDAY LECTURE

PELORUS, PARALLEL RULERS, THE LEAD, SOUNDING MACHINE, DIVIDERS AND LOG

_I. The Pelorus_

This is an instrument for taking bearings of distant objects, and for
taking bearings of celestial bodies such as the sun, stars, etc. It
consists of a circular, flat metallic ring, mounted on gimbals, upon a
vertical standard. The best point to mount it is in the bow or on the
bridge of the ship, where a clear view for taking bearings can be had.
The center line of the pelorus should also be directly over the keel
line of the ship. The inner edge of the metallic ring is engraved in
degrees--the 0 deg. or 360 deg. and the 180 deg. marks indicating a fore-and-aft
line parallel to the keel of the ship. Within this ring a ground glass
dial is pivoted. This ground glass dial has painted upon it a compass
card divided into points and sub-divisions and into 360 deg.. This dial is
capable of being moved around, but can also be clamped to the outside
ring. Pivoted with the glass dial and flat ring is a horizontal bar
carrying at both of its extremes a sight vane. This sight vane can be
clamped in any position independently of the ground glass dial, which
can be moved freely beneath it. An indicator showing the direction the
sight vane points can be read upon the compass card on the glass dial.
If the glass dial be revolved until the degree of demarcation, which is
coincident with the right ahead marking on the flat ring, is the same as
that which points to the lubber's line of the ship's compass, then all
directions indicated by the glass dial will be parallel to the
corresponding directions of the ship's compass, and all bearings taken
will be compass bearings, i.e., as though taken from the compass itself.
In other words, it is just as though you took the compass out of its
place in the pilot house, or wherever it is