The pilots were all Indians, and they used the forestaff and quadrant for their observations.
The first root after zero is thus in the third quadrant, corresponding to m =1.
The old method of giving quadrant elevation by clinometer was obviously too slow.
1) is a wooden quadrant in.
420) of a change of form in the Greenwich mural quadrant led to the introduction of astronomical circles at the Royal Observatory, and to his own appointment as its head.