Found at an estate sale, this vintage yellow Pickett N4-ES Large 4ft Store / Classroom Display Wood Slide Rule is 4’ long, 9” wide, and weighs 4 lbs. 3 oz. The cursor is 10” wide.

This vintage classroom slide rule is in good condition. The slide moves freely and so does the cursor. Made of wood, this large slide rule probably dates from the early 1950’s. It has unfortunately acquired some scrapes in the paint here and there over the years (see photos). Most of these defects are inconspicuous. I have temporarily wrapped strips of wax paper around the braces to ensure that the slide won’t scrape against them.

This is a Pickett and Eckel MODEL N4-ES LOG LOG Vector Hyperbolic Dual-Base SPEED RULE™ (see photos). One end says PICKETT & ECKEL INC., CHICAGO 3, ILL. U.S.A. 300. The end with the Pickett logo says 306. I understand that “300” and “306” are identification numbers for the artwork.

The scales are:

Front: LL1+.00D/-.00D, LL2+.0D/-.0D, DF/m [ CF/m, TH, SH1, SH2, L, <CI, C ] D, LL3+.D/-.D, LL4+D./-D.

Back: 3√ #1, 3√ #2, 3√ #3, DF [ CF, T1, T2, ST, S Cos,  <CI, C ] D, <DI, √ #1, √  #2