A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Iwancio
Date: 2020 Jan 14, 14:33 -0800
Early editions of HO 229 came with a transparent insert ("diagram C") used for interpolating LHA and latitude graphically. Later reprints removed it and the related diagrams A & B from volumes 1-4, keeping them only for the volumes covering high latitudes. There's mention of them (and their removal) in the preface of the newer editions, on page III.