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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Murray Buckman
Date: 2020 Nov 2, 08:50 -0800
We know that he was baptised on January 9, 1828. We can safely assume he was born late in 1827. I have found a secondary source reference to 1827 but with no actual birth date. Here is a link to the date of baptism and some brief biological information. (Page 291 if the full link does not work).
https://books.google.com/books?id=pNs8AAAAIAAJ&pg=PA291&lpg=PA291&dq=Alfred+Challice+Johnson
This is consistent with the earlier post here:
http://fer3.com/arc/m2.aspx/C-Johnson-Davies-jan-2017-g37807
He was alive in 1907 because he signed the foreword to the 5th edition of "How to find the time at sea in less than a minute" as "Dartmouth 1907". Bibliographies give a year of death of 1909 - without a month and day.
So it would appear that his life stretched from George IV, through William, Victoria and into Edward VII.
Murray