AZIMUTH BY HOUR ANGLE/ALTITUDE

Correct bearing to an RO could be determined by;

1. Observing and plotting the star or sun’s movement through theodolite.
2. Noting the precise time of observation and expressing it as Greenwich Mean time
3. Recording the star or sun’s vertical inclination and horizontal angle to the RO
4. Applying the recorded results to the form
5. Work through the set steps and formulae and with reference to the Star Almanac we could determine correct bearing to the RO.

Azimuth by Altitude Record Sheet

STAR ALMANAC

This was a set of tables listing the position of the sun and clearly visible stars for each day of the year. It listed the right ascension or the celestial coordinates corresponding to earth’s longitude and the declination the celestial coordinates corresponding to earth’s latitude, both pinpointed by a precise Greenwich Mean Time.

Our interest in the Almanac lay in the fact that if we knew our own position’s coordinates and we could determine the sun or star’s position in relation to our maps, we could determine correct bearing from it.

1992 Land Surveyor's Almanac example of tables used to calculate bearing from sun or star observations. Almanac offered courtesy J I Noad, Inverell