SCIENTIFIC INSTRUMENTS CO., Berkeley, California / USA (1962) ************************************************************* Made in Japan S C A L E S of the CIRCULAR SLIDE RULE » SCI Model 120 « ============================================================= Front Side Back Side ============================================================= L lgX K X3 DI 1/X A X2 D X D X outer circles T1 tan(X) ----------------------------------------- S1 sin(0.1X) C X inner circles T2 tan(0.1X) CI 1/X S2 sin(0.01X) EI sqrt( CI = 1/X < ODD-No-Digits > ) T3 tan(0.01X) sqrt( CI = 1/X < EVEN-No-Digits > ) ST arc(0.01X) REMARKS: ============================================================= This Circular Slide Rule was the greatest bargain in the Bay Area's huge ALAMEDA FLEA MARKET in May 2006 - it was free! We got back our purchase price because it fall apart as the seller put it in the bag... It was dirty, had two broken cursors and a missing center screw. The cursors are now made of PVC and reinforced at the ends with slices made from a cat food can. The hairlines are made with a sharp » X-ACTO « and colored with a permanent marker. Historical Remarks ... impressum: ************************************************************* © C.HAMANN http://public.BHT-Berlin.de/hamann 12/15/06 |