Albert Nestler, Lahr in Baden / Germany                          (1925)
***********************************************************************
                                                            VERSION (A)

S C A L E S   of  the   N E S T L E R   » K A U F M A N N «    Model 40  
=======================================================================
Front Side            [ inverse / RED ]                       Back Side
=======================================================================
( 0 ...  28 cm Ruler )

q         %
Z         X           Z = Zinsen  ( = Interest )
-----------------------------------------------------------------------
T         X           T = Tage    ( = Days )         CONVERSION SCALE :
[R]       [1/X]                                           £ = Pound
[M]       [ Metric / Inch Conversion ]                    s = Schilling
D         %           D = Discount = 360 / p %            d = Pence
-----------------------------------------------------------------------
K         X           K = Kapital ( = Capital )
L         lnX

( 0 ... 11" Ruler )

R E M A R K S :                  There are 2 Model 40 in the Collection
=======================================================================
Scale D is keyed to Scale T at  x = 3.6  ( = 1% for 1 Year = 360 Days )

Here the (German-) formulas & translations:

   Z = ( K * p * n )/100 ;   n = Jahre = Tage/360

(  Z = Interest; K = Capital; p = Interest Rate; n = Years; T = Days )
( ZZ = Zinseszins = Compound Interest = K * qn ,  q = 1 + 0.01 * p )

Historical Remarks ...

The slide rule is made of mahogany with scales on celluloid veneer.  On
the back side is a table with conversions & formulas.  It was found in
bad shape without cursor.  The CURSOR is now home-made of aluminum with
a window of PVC from a CD case.  The hairline is made with a  »X-ACTO«
and colored with a marker.  "MouseOver" the cursor in the picture above
to get DETAILED VIEWS of it ...

                   Have a look at the Newer Version (B)
impressum:
***********************************************************************
© C.HAMANN         http://public.BHT-Berlin.de/hamann          01/01/10