A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Tony Oz
Date: 2019 Dec 21, 12:08 -0800
Dear Mike, Seasons Greetings!
Yes, it was exactly the "clever bit" that excited me. :)
Before that booklet find I spent quite some time drawing the parallels and meridians, the compass roses, etc. As it transpired - all theese lines are not essential!
Besides, the method also takes care of the movement of the observer - for free. Otherways one has to consult a MOB-correction table or do some calculations, or advance the first PL. It is all accounted for by drawing the TC line and marking the distance travelled between the sights.
But THE jewel idea of cutting a latitude difference segment with a line drawn at an AP latitude angle to find the longitude difference - that is THE marvel there.
From then on I do not bother about either factory-printed or home-brew plotting sheets. I just use any decent piece of paper for plotting.