A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David C
Date: 2020 May 3, 16:45 -0700
Which copy/ies of the Admiralty Navigation Manual (ANM) were you comparing the 1922 review with?
The Admiralty was subsumed into the Ministry of Defence in 1964. When I mention the AMN I am thinking of volumes issued between 1914 and 1964. The earliest copy I have is 1922 volume 2., the latest are 1964 vols 1 and 2. In between I have various copies of vol1, vol2 and vol3. I did find a copy of the original 1914 edition but was too slow to buy it.
To give you an example of my problem - I am researching the formulae for calculating azimuth. Over the years I have become confused with the various versions. If I go to Bowditch 1958 and 1995 I can find the formulae. There are three of them, depending on the input arguments - d t l, d h l, and d h t. Presumably there is a formula for h l t but I have not found it. If I go to my copies of the AMN can I find these formulas. No! I did find a haversine formula in an example but it appeared out of thin air. It seemed to be assumed that the reader already knew the formula. I have the impression that the AMN is designed for qualified naval officers, not those learning. This is consistant with comments made in the review by R. T. G.
If you can point me to a volume and page that summarises the azimuth formulas I may change my opinion of the AMN (-;