Don Casey - Dragged Aboard Storm Tactics Handbook:
Modern Methods of Heaving-To for Survival in Extreme Conditions
by Lin Pardey and Larry Pardey


      

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Re: Mirror problem

From: Alexandre E Eremenko (no email)
Date: Sat May 06 2006 - 10:11:22 EDT

  • Next message: George Huxtable: "Re: Mirror problem"

    Dear George,

    > If you would kindly
    > copy it and resend, I would be grateful.

    It takes a lot of effort to find some old message in
    the Nav-L archiv. Your current message is almost OK
    with its 72 character lines.
    You will make my replying to
    you even easier if you reduce them to 50 characters:-)
    The shorter lines are easier to read, do you agree?

    That's why the lines in my messages are always so short.
    (The editor I use does not insert them automatically,
    I just type
    a line break
    wherever I want).

    Back to the Nav business.

    > Other adjustments, for side error and
    > index error, will be made to the horizon mirror.

    I thought this is a standard arrangement, have you seen sextants
    where the side error is adjusted on the index glass??

    > The mirror should be held at an
    > angle in the view of the telescope, close in front of the objective,
    > with some arrangement of cardboard and sticky-tape.

    Of course, I can experiment with my spare mirror this way.
    But if the mirror is bent as a result of the way it is attached
    to the sextant, the only way to find this out is to fix the
    whole sextant, without detaching the mirror.

    > the sort of skill that was once expected
    > of physics research students, in the days before they devoted themselves
    > entirely to computer screens. That's an under-appreciated gift, and I
    > bet you have it.

    I am afraid I don't. Actually this is one of the reasons
    why I became a mathematician rather than a physicist or an engineer.
    I was equally attracted to physics and mathematics, but knew that
    I am not a handy man to make ingenious experiments,
    so I thought it is better to choose math.

    Alex.


  • Next message: George Huxtable: "Re: Mirror problem"



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