NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Borrowed Bygrave
From: Gary LaPook
Date: 2016 Jan 15, 02:06 +0000
From: David Pike <NoReply_DavidPike@fer3.com>
To: garylapook@pacbell.net
Sent: Thursday, January 14, 2016 5:17 PM
Subject: [NavList] Borrowed Bygrave
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From: Gary LaPook
Date: 2016 Jan 15, 02:06 +0000
Obviously, my explanation is the best way to operate the Bygrave, better than the original manual which doesn't address some special cases.
I was able, by pre-arrangement, to see several of them at the Science Museum storage facility in London in 2009.
From: David Pike <NoReply_DavidPike@fer3.com>
To: garylapook@pacbell.net
Sent: Thursday, January 14, 2016 5:17 PM
Subject: [NavList] Borrowed Bygrave
I’ve got the loan of a Bygrave Position Slide Rule MkIIA from the Royal Institute of Navigation for a couple of months (photos below). Apparently, they had two, a good one and a poor one. Unfortunately, I was only able to find the poor one; nobody seemed to know what happened to the good one. It carries the inscription that it was produced by the Air Ministry Laboratory South Kensington in August 1920. If the number was ever filled in, it’s long since rubbed off. I’d like to teach myself to use it prior to possibly making a copy for myself with plastic piping. Is the best set of usage instructions those on Gary’s Freddie Noonan page? Also, does anyone know where I can find a photo or print out of the explanation off the side of the MkIIA? Finally, does anybody know what went down the inside of the cylinders? All I can see is the remains of a brass chain. DaveP
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