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    Re: Bygrave Scale Lengths
    From: Hewitt Schlereth
    Date: 2013 Jan 30, 11:03 -0800

    Brad, it's been a long time since I did translations from German and I have 
    never had hands on any cylindrical slide rule, in but the phrase,
    "Bei d nahe 0 oder t nahe 0 und 90  verwende F-Tafel",
    the verb "verwende" means 'use' or 'employ' an 'F-Table', which I would take 
    to mean something ancillary to the main slide rule, like say a printed table.
    Sent from my iPad
    On Jan 30, 2013, at 6:21 AM, "Brad Morris"  wrote:
    > Hi Gary
    > Image 122161.img_2160.jpg tells the tale!
    > In it, we see the rules for using the device.  Within those rules, we see
    > the standard admonishments for the MHR1, with one major and glaring
    > change.  In German, we have:
    > Bei d nahe 0 oder t nahe 0 und 90  verwende F-Tafel
    > Which I loosely translate to:
    > Do not use the slide rule (F-Tafel) when declination is near zero deg or
    > when the hour angle is near 0 or 90 deg.
    > The is no longer any numerical prohibition like 0 deg 20 min or 89 deg 40
    > min.  It just says "near" (nahe).  This could be understood to say the same
    > thing, since 20 min is near to zero.
    > But given the precise directions of the MHR1, I would like to think that
    > near now means that the scale has been extended downwards and upwards, as
    > we have discussed, towards 0 and 90 deg.  To what value?  The images do not
    > reveal this data point.  Pity.  I'd like to think that it went to within an
    > arc minute, the trick of a tiny offset to include 0 deg 90 deg not
    > withstanding.
    > What do you make of the conversion table, the adjustment knobs and the
    > magnifying glass?  Magnifiers are typically associated with verniers and
    > fine graduations.
    > Regards
    > Brad
    > On Jan 30, 2013 12:39 AM, "Gary LaPook"  wrote:
    >> ------------------------------
    >> I am attaching some photos I took of the MHR2 in London in 2009.
    >> gl
    >> +++++++++
    >> I would be very curious to see what the scale lengths and operating ranges
    >> of the MHR2 table top calculator. Ronald - Do you know these values?
    >> ++++++
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    >> >> *Attached File: 122161.img_2160.jpg >> * >> *Attached File: 122161.img_2161.jpg >> * >> *Attached File: 122161.img_2162.jpg >> * >> *Attached File: 122161.img_2164.jpg >> * >> *Attached File: 122161.img_2166.jpg >> * >> *Attached File: 122161.img_2167.jpg >> * >> *Attached File: 122161.img_2168.jpg >> * >> *Attached File: 122161.img_2169.jpg >> * >> >> View and reply to this message: http://fer3.com/arc/m2.aspx?i=122161 >> > > > > > View and reply to this message: http://fer3.com/arc/m2.aspx?i=122166 > >

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