Albert Nestler, Lahr in Baden / Germany (1925)
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S C A L E S of the N E S T L E R » RIETZ « Model 23
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Front Side Back Side
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( 0 ... 25 cm Ruler )
K X3
A X2
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B X2 S sin(0.01X); sin(0.1X)
C X T tan(0.1X)
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D X
L lgX
( 1:25 Ruler )
R E M A R K S : ( 1° = 60' ; 1' = 60" )
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The TRIGONOMETRIC SCALES are divided in MINUTES(') & SECONDS(")
S keyed to A/B ; T keyed to C/D
On the back side is a ( worn-out ) table with physical constants.
In the INNER BODY of this historic mahogany RIETZ SR are 2 PATENT-
NUMBERS engraved 173660 (=Nestler,1905) & 181110 (= M.Rietz,1902),
and NO MODEL NUMBER ! But the SR came in a cardboard case with the
INSCRIPTION » No.23 Nestler's System Rietz D.R.P. No.173660 «
The CURSOR GLASS was broken. It had to be replaced by a HOME-MADE
of PVC from a CD-Cover - The HAIRLINE is made with a sharp
»X-ACTO« and colored with a permanent marker. "MouseOver" the
cursor in the picture above to get a DETAILED VIEW of it ...
Historical Remarks ...
impressum:
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© C.HAMANN http://public.BHT-Berlin.de/hamann 06/20/11
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