bearing is what is known as the "bow and
beam" bearing, and is the standard method used in coastwise navigation.
Any one of these methods is of great value in fixing your position with
relation to the land, when you are about to go to sea.
4. Sextant angles between three known objects.
This method is the most accurate of all. Because of its precision it is
the one used by the Government in placing buoys, etc. Take three known
objects such as A, B and C which are from 30 deg. to 60 deg. from each other.
[Illustration]
With a sextant, read the angle from A to B and from B to C. Place a
piece of transparent paper over the compass card and draw three lines
from the center of the compass card to the circumference in such a way
that the angles secured by the sextant will be formed by the three lines
drawn. Now take this paper with the angles on it and fit it on the chart
so that the three objects of which angles were taken will be intersected
by the three lines on the paper. Where the point S is (in my diagram)
will be the point of the ship's position at the time of sight. To secure
greater accuracy the two angles should be taken at the same time by two
observers.
5. Using a compass, log and lead when you are in a fog or unfamiliar
waters.
Supposing that you are near land and want to fix your position but have
no landmarks which you can recognize. Here is a method to help you out:
Take a piece of tracing paper and rule a vertical line on it. This will
represent a meridian of longitude. Take casts of the lead at regular
intervals, noting the time at which each is taken, and the distance
logged between each two. The compass corrected for Variation and
Deviation will show your course. Rule a line on the tracing paper in
the direction of your course, using the vertical line as a N and S
meridian. Measure off on the course line by the scale of miles in your
chart, the distance run between casts and opposite each one note the
time, depth ascertained and, if possible, nature of the bottom. Now lay
this paper down on the chart which can be seen under it, in about the
position you believe yourself in when you made the first cast. If your
chain of soundings agrees with those on the chart, you are all right. If
not, move the paper about, keeping the vertical line due N and S, till
you find the place on the chart that does agree with you. That is your
line of position. You will never find in that locality any other pla
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