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    Re: The Bygrave Slide Rule
    From: Ronald van Riet
    Date: 2009 May 28, 01:45 -0700

    Please read my full story on the Bygrave which can be found in the
    archives of this group.
    tan and cotan could be easily changed because one is the reverse of
    the other, but this can not easily be done with sine and cosine,
    because here the relationship is more complex. The outer tube clearly
    is cosine. If you now read the inner tube it must be cotan as
    explained in the article.
    On May 27, 11:57�pm,  wrote:
    > I am posting here now because I believe that some of the recent writings on
    > the internet about the BSR may be misleading. I refer to the assertion by
    > Gary LaPook (GLP) and Ron van Riet (RVR) that the inner scale of the BSR is
    > actually a cotangent scale and not a tangent scale. The patent application,
    > and the original manual of the BSR talk about tangents, so RVR and GLP seem
    > to be suggesting that Bygrave may have made a mistake somewhere, even if
    > only in the documentation. �It seems quite reasonable to me that this scale
    > can be described as a tangent scale. I think I can explain why this question
    > arose in the first place.
    Navigation List archive: www.fer3.com/arc
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