GEBR. WICHMANN, Berlin / Germany (1925) **************************************************************** made by Albert Nestler, Lahr in Baden / Germany SCALES of the W I C H M A N N » R I E T Z « Model 474 ================================================================ Front Side [ inverse / RED ] Back Side ================================================================ ( 0 ... 28 cm Ruler ) A X2 ---------------------------------------------------------------- B X2 S sin(0.01X); sin(0.1X) [CI] [1/X] L lgX C X T tan(0.1X) ---------------------------------------------------------------- D X ( 0 ... 29 cm Ruler ) R E M A R K S : ( 1° = 60' ; 1' = 60" ) ================================================================ The TRIGONOMETRIC SCALES are divided in MINUTES(') & SECONDS(") S keyed to A/B ; T keyed to C/D The slide rule is made of pear wood with scales on celluloid veneer. On the back side are physical & technical constants. In the body under the slider is a 30 ... 55 cm ruler and a print » A.N.A.G. « , an indicator for made by » A.NESTLER AG « - The blind print » 25 « on the side gives the production year ? Historical Remarks ... impressum: **************************************************************** © C.HAMANN http://public.BHT-Berlin.de/hamann 06/13/10 |