A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Michael Bradley
Date: 2016 Aug 17, 13:05 -0700
'The 6 page Ageton Classic table also doubles as a log table for solving the Hav Doniol multiplication step. Carrying a 5 page natural haversine table along with the 6 page Ageton Classic table gives the CN navigator 3 different ways to perform 1' precision sight reduction from the DR position. The 11 pages total fits easy into the nautical almanac and can be used as a daily page book mark.'
Very sweet indeed, thanks, but I'm fumbling towards another destination: setting myself the target of using the same method for precision 0.1 minute CN as for so called emergency 1 minute CN. Hav/Doniol suits. No special cases, no decisions to make, no unneeded columns or rows in the look up tables, just wind the same handle, every time, procedure wise.
!983 Nories gives me 5 figure natural haversines and 5 figure logarithms, which go with the Nautical Almanac for 'precision' CN. 2 reasonable size books.
Hanno Ix's 4 page natural haversine table and a four page set of graphical 4 figure logarithms will do very nicely for the 1 minute CN reduction with the Sun and Aries Long Term Almanacs, for what we are calling emergency use, just additions and subtractions to go with the look ups. No books at all, just a few laminated back to back sheets hitched into the back of home brew log sheets, along with other reference sheets.
Apropos the hitching. I'm confident I'm not alone in finding that the need to keep referencebooks open on a small boat's chart table comes as a minor unneeded hassle. In my mind's eye I can see Gary with his flat Bygrave and today's almanac sheets printed from the Air Almanac. All flat, no books needed. Excellent. Similarly hitched up open flat Hav/Doniol chart table resources suit me.
In Britain we call a short piece of string terminated at each end with a small crosswise metal toggle bar a 'Treasury Tag'. Very good for making open flat home brew documentation, laminated or not. What do you call such a piece of string in California?