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Re: Why a silver index scale?
From: Bill Morris
Date: 2016 Mar 27, 10:00 -0700
Geoffrey
Bill Morris
From: Bill Morris
Date: 2016 Mar 27, 10:00 -0700
<<but why was Hughes & Son still using silver arc during the 1940s when these regards were certainly not true any more. Silver is expensive. Pewter, on the other hand, is a lot cheaper and would (I submit) do the job just as well...?>>
Geoffrey
This is a question that I too have asked myself several times. I have wondered whether the "silver" arc of Hughes micrometer sextant was perhaps nickel silver, a brass with 20 percent nickel substituted for for sinc, but I have also heard a tale of a war surplus lot of their sextants having been bought to be stripped of the silver arc and then scrapped. I will see if it tarnishes with a drop of bleach and report back.
Bill Morris
