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KEUFFEL & ESSER   POCKET   4097_D
( 5" / 12.5 cm Scales )





KEUFFEL & ESSER, New York / USA        SN = 130526         (1950)
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                                                      VERSION (B)

S C A L E S   of   the      »  P O C K E T  «        Model 4097_D
=================================================================
Front Side          [ inverse / RED ]                   Back Side
=================================================================
                                               ( 0 ... 5" Ruler )
A        X2
DF       πX
-----------------------------------------------------------------
CF       πX                           S     sin(0.01X); sin(0.1X)
                                      B     X2
[CI]     [1/X]                        L     lgX
C        X                            T     tan(0.1X)
-----------------------------------------------------------------
D        X
K        X3                                 ( 0 ... 13 cm Ruler )

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

S keyed to B  ( on BACK SIDE !);  T keyed to C/D

This  Celluloid  Pocket-SR  was found  in a  Flea-Market  with  a
broken Cursor-Window.  Replacement is made of PVC from a CD-Case:
The Hairline is made with an  »X-ACTO«  and colored  with a black
Permanent-Marker.

There is an  OLDER  VERSION (A)  in the Collection
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with an  O L D E R   L O G O  and  SN = 52934  ...

      

                     Historical Remarks ...
impressum:
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© C.HAMANN      http://public.BHT-Berlin.de/hamann       10/11/12