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    Re: Bill Morris' MHR1 reproduction
    From: Geoffrey Kolbe
    Date: 2021 Jun 12, 07:02 -0700

    I wrote an article a while back: Geoffrey Kolbe, "The Bygrave Slide Rule Revisited", The Navigator's Newsletter, Issue 93, Fall 2006. in which I describe a Bygrave held in the Science Museum storage facility, and a cardboard-copy I made to see how well it worked.

    Here is a picture of my 'cardboard-copy' of the Bygrave slide rule, which is basically made using a collection of cardboard tubes. It works pretty good and the accuracy is around 1-2 MOA, which is what is claimed for the original Bygrave. It is a hi-res photo taken with my tricorder (which includes my communicator so it does not have to be a separate device), but I am sure Frank will massage it suitably.


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