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    Resilvering sextant mirror, 1919
    From: Paul Hirose
    Date: 2019 Mar 1, 21:00 -0800

    I came across some instructions for resilvering a sextant mirror in a
    1919 issue of the US Naval Institute Proceedings. Some of the supplies
    may be hard to find nowadays, such as the tinfoil wrapper on a pack of
    cigarettes.
    
    "At present when ships are making long sea voyages, frequently the
    navigator will find that his sextant mirrors are going bad and no spares
    available. He is also apt to find his sextant mirrors in such condition
    that although the sun can be handled, great difficulty is encountered
    with stars."
    
    https://books.google.com/books?id=sX-kfItGYgYC&jtp=245
    
    There's also a sight reduction article. "When one must work in a sweat
    box, such as a chart house becomes when the ship is darkened, any method
    that shortens the work at that time is most welcome. Though there is
    nothing startling in the following process, it is something that no
    navigator I have met has used, and one of which none of the younger
    officers I have come in contact with have ever heard... The process is
    simply to combine, before sunset, all the elements of the work of the
    haversine formula possible, leaving very little to do after star sights
    are taken."
    
    https://books.google.com/books?id=sX-kfItGYgYC&pg=PA41
    
    An article on "Feed Water Temperature" by P.V.H. Weems shows that his
    interests were not confined to navigation.
    https://books.google.com/books?id=sX-kfItGYgYC&jtp=383
    
    "The Crossing of the Atlantic by Air" makes an argument for the airship,
    the author demonstrating mathematically that a crossing by airplane
    would be a freak occurrence. His estimates of starting fuel (3 tons, or
    830 Imp gal) and ground speed (120 kt) for a notional airplane are
    remarkably close to the values for the successful flight a few months
    later. But he estimated 13.4 flight hours until fuel exhaustion, while
    Alcock & Brown flew 16 hours and still had a fuel reserve when weather
    forced them down.
    https://books.google.com/books?id=sX-kfItGYgYC&jtp=459
    
    Tables of contents from the 1919 volume:
    https://books.google.com/books?id=sX-kfItGYgYC&pg=PP17&focus=viewport
    https://books.google.com/books?id=sX-kfItGYgYC&pg=RA1-PA184-IA5&focus=viewport
    https://books.google.com/books?id=sX-kfItGYgYC&pg=RA1-PA316-IA5&focus=viewport
    https://books.google.com/books?id=sX-kfItGYgYC&pg=RA1-PA492-IA5&focus=viewport
    https://books.google.com/books?id=sX-kfItGYgYC&pg=RA1-PA718-IA5&focus=viewport
    https://books.google.com/books?id=sX-kfItGYgYC&pg=RA1-PA876-IA13&focus=viewport
    

       
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