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    Ruminatons on Bygrave and Hohenrechenschieber scale markings
    From: Brad Morris
    Date: 2013 Feb 17, 23:14 -0800

    Hi Robin

    Linked, please find the survey results.

    I draw your attention to the unexpected artifacts found on the (co)tangent scale. There is a new mark "G", which appears in only two places. In one place, where an E was expected, we have a C. The details are in the survey. It is my view this lends credence to the view that the scales were hand drawn. That can be the only explanation for these 'errors' or artifacts. Machines don't make mistakes like this, people do!

    If your drawing is to scale, then A must be taller than 4/100". If not to scale, then leave it at 4/100". It just doesn't appear to be the right visual ratio in your presentation It could be 5/100" or 6/100". It was dang hard to measure those lines.

    The ball is touching the line D. It does not float just above the line, it touches it. In the case of G, the top of the line forms a chord across the ball such that there is no gap.

    Please note that the survey results are just for MHR1 werk-nr 90176. I make no claims as to any other instrument.

    This survey was exhausting as well as exhaustive. Thanks for the gentle shove.

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