From: David Pike
Date: 2020 Aug 16, 12:06 -0700
A couple of questions:
1. Why would anyone wish to redact the sextant pattern and number from the certificate, unless they didn’t match the sextant in the box.
2. What did S I R S stand for? Sextant Instrument Repair Shop possibly.
I did find a better photo from 1981, https://www.catawiki.com/l/16820367-sextant-pattern-491-hughes-and-son-london-circa-1950 so it’s the way the ACO must have been doing things around that time. I visited them in January 80 or 81 to swap a Watts Datum Compass; they had to be delivered by hand. It seemed very interesting in the Compass Dept, but I never thought to ask to look at the Sextant Dept. DaveP