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    Re: Double Altitude - Sensitivity to Time Interval
    From: David C
    Date: 2016 Dec 5, 11:38 -0800

    The comment about differential calculus was a throw away line that came into my head as I was writing the post.

    The small time interval is because I was trying a method quoted by Cotter. He stated that  some writers (referring to 19th century text books)  recommended observing the sun (when due east or wes) rising or falling one diameter. This required ony one setting of the sextant. I think I have proved to myself that the method is of no practical use. Clearly it could not be used on a moving vehicle.  If you were lost in the desert and had a means of measuring alt, knew where east was and could count seconds accurately you could maybe find lat to within a few degrees - John Wayne or McGiver?

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