Albert Nestler, Lahr in Baden / Germany (1930) *********************************************************************** VERSION (B) 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 ... 27 cm Ruler ) Z X Z = Zinsen ( = Interest ) ----------------------------------------------------------------------- T X T = Tage ( = Days ) LL1 exp(0.01X) [R] [1/X] LL2 exp(0.1X) D % D = Discount = 360 / p % LL3 exp(X) ----------------------------------------------------------------------- K X K = Kapital ( = Capital ) ( 1:5 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 came in a WOODEN BOX. It is made of mahogany with scales on celluloid veneer. On its back side are (worn-out) conversion tables & formulas. To use the LL-SCALES, the slider has to be turned. NESTLER & "MODEL 40" are faded, but to read as BLIND PRINTS under the slider. The restoration took longer than expected ... The box and the slide rule came in bad shape: The box was splittered & the scales were dirty, scratched and partly broken, partly not glued. The cursor was a NESTLER, but not the original: Faded 4 hairlines are useless, because no SquareScale for Diameter/Area-Relation exist here. After cleaning, only the center hairline was restored. Have a look at the Older Version (A) impressum: *********************************************************************** © C.HAMANN http://public.BHT-Berlin.de/hamann 04/21/09 |