A slide rule for every purpose: 4031 4051 (20" Mannheim) 4053-3 4054 4058 C 4071-3 4092-3 4092-5 (20" Log Log) 4097 C 4098 A 4153-1 4181-1C Unnumbered 8-inch rule Doric 68 1210 (Log Log Duplex Decitrig) Deci-Lon 10 K-12 Prep

· There's a K&E slide rule for every purpose. Whether designed to meet the modest needs of the beginner or the exacting require- ments of professionals, all K&E rules feature "built in" accuracy and reflect the skill and craftsmanship of America's most experi- enced slide rule manufacturer KEUFFEL & ESSER CO. EST. 1867 NEW YORK · HOBOKEN, N. J. Chicago · St. Louis · Detroit · San Francisco · Los Angeles · Montreal

Penn State Engineer, October, 1953