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FREDERICK  POST   » 1442 «
Dual  10"/5"  POCKET-SlideRule






FREDERICK POST CO., Chicago, Illinois / USA               (1944)
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SCALES of the  P O S T   » 1442 «   Dual 10"/5" POCKET-SlideRule
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Front Side                          [ in RED ]         Back Side
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K       X3                                      Conversion Table
A       X2                                  Fractions-to-Decimal
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B       X2                           L         lg(X1); [lg(X2)]
S       sin(0.1X); sin(0.01X)
T       tan(0.1X)                   [C2]      [X2]
C       X                            C1        X1             *)
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D       X                            D1        X1  =  sqrt(X)
DI      1/X                         [D2]      [X2] = [sqrt(10X)]
                                     D         X

R E M A R K S :                       (  1° = 60' ;   1' = 60" )
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The  TRIGONOMETRIC  SCALES  are   in   MINUTES(')  &  SECONDS(")

S keyed to A/B ;  T keyed to C/D

This SR has a mahogany body with celluloid scales and a molded
acrylic cursor. The SR came in an artificial leather case.

 *) It is a Dual 10"/5" POCKET-SlideRule, because ...
 
    Scales  C1/D1            1 ..  X1  .. sqrt(10);
    Scales [C2/D2]    sqrt(10) .. [X2] .. 100

    and     D = X ;    X1 = sqrt(X) ;    [X2] = sqrt(10X)

    ... Therefore this 5" POCKET has the PRECISION of a 10" SR

The INSTRUCTION MANUAL ( 14 pages ) can be downloaded from ...

    http://www.sliderulemuseum.com/Manuals/M155 ... pdf

Compare the SCALE DESIGN with
    the NESTLER »PRAEZISION«,
    the »WICHMANN-1417« ( made by A.N. = Albert Nestler),
    the FABER-CASTELL »COLUMBUS/A.Rohrberg« and
    the FABER-CASTELL »NOVO-DUPLEX«

                  Historical Remarks ...
impressum:
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© C.HAMANN   http://public.beuth-hochschule.de/~hamann   12/10/13