There are occasions when it can be useful to plot bearings from objects not shown on the chart, for example a radiobeacon or a lighthouse outside the coverage of the chart in use. The traverse table may be used for this purpose in the following manner:

1. Establish the latitude and longitude of the object (radiobeacon, lighthouse, &c).

2. Choose a convenient latitude from which to plot the bearing and calculate the difference of latitude between it and the object.

3. With the bearing as course extract from the tables the departure corresponding to this d. lat.

4. For the middle (or mean) latitude derive the corresponding d. long. and apply it to the longitude of the bearing object.

5. Plot the bearing, as a position line, through the chosen latitude and the longitude thus derived.