A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2016 Jan 6, 10:24 -0800
Thanks for this post. It is worth pointing out that Ageton used 1/cos and 1/sin logs to solve a split spherical triangle. I believe it was Napier who did the early work many centuries ago on spherical trig which paved the path to the trig formula most commonly used to solve the single spherical triangle by calculator today. A recent stumble on my part last year lead to the Ageton tables also being able to efficiently solve the single spherical triangle for Hc and azimuth.
The K&E slide rules are nice. I own the 4080-3, 4070-3, Doric 10", and Doric 6" models. They all have very smooth slides. Looking forward to trying your purposed navigation slide rule. Aluminum may not be the best slide rule material. 3D printers can use almost any material now. I'm thinking carbon fiber or titanium.