FOWLER's Long-Scale Vest-Pocket Calculator SN = 11726
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FOWLER & Co., Manchester / England w.Metal-Case ( 1900 )
Diameter = 2 11/16 " (68 mm); Thickness = 7/16" (11 mm)
The KNOB WITH RING turns the m o v a b l e FRONT SCALE
The OTHER KNOB turns (1st) the POINTER on FRONT SCALE
(2nd) m o v a b l e BACK SCALE
FIXED INDEXES are under the "RING" KNOB on BOTH SCALES
Front Scales:
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(a) An outer "Short" (7 1/2 ") Circular Scale 1 ... 10
(b) Six inner Circles form a "Long" (30") Scale 1 ... 10
Back Scales:
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(a) Outer "Short" (7 1/2 ") Circular Scale 1 ... 10
(b) 1/X 10 ... 1
(c) lg(X) 0.01 ... 1
(d) sqrt(X) 0 ... 100
(e) sin(0.1X) 5°45' ... 90°
(f) tan(0.1X) 5°45' ... 45°
(g) sin(0.01X) 35' ... 5°45'
S H O R T INSTRUCTION for Calculations on F R O N T SCALES
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LIST OF ABBREVIATIONS: M = Middle knob turns front scales
R = Knop ON THE RIGHT turns
C = Cursor on front
H = Hairlines are fixed
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MULTIPLICATION 2*3*4 = 24 Set X=2 under H with M
Set C on X=1 with R
Set X=3 under C with M
( Read X=6 under H )
Set C on X=1 with R
Set X=4 under C with M
RESULT: Read X=24 under H
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DIVISION 6/3 = 2 Set X=6 under H with M
Set C over X=3 with R
Set X=1 under C with M
RESULT: Read X=2 under H
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R E M A R K S T O R E S T O R A T I O N ...
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One GLASS WAS CRACKED. The decision was made to replace both
glasses with PVC from a CD-Case. Hairlines are made with an
»X-ACTO« and colored with a marker in RED ==>> The advantage:
FIXED POINTERS are RED, the MOVABLE POINTER is (orig.) BLACK.
impressum:
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© C.HAMANN http://public.BHT-Berlin.de/hamann 02/24/10
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