Scope and ContentPeriodical: The Slide Rule. Volume 1, No. 2 and No. 4, 1925. Published by Keuffel & Esser Co., Hoboken, N.J. Each is a single folio, [4] pp., 5-1/2" wide x 8-1/4" high. No. 4 has ink stamp on page [1], Jan 2, 1926. PDF of each issue on file. Promotional / educational publication by the company whose main office and factories were in Hoboken at this time. Page [4] of number 2 has code "4647" and number 4 has "5051". Vol 1, no. 2, page [1]: "Up in the Air." Photo aboard the U.S.N. Airship (blimp) Los Angeles showing two officers, one using a slide rule. Short article below. Vol 1, No. 2, pg [2-3]: The Slide Rule in Chemistry; The Chemist's Duplex Slide Rule. Vol 1, no. 2, page [4]: The Origin of the Slide Rule. Vol 1, no. 4, page [1]: "Woman Teachers Make Use of the Slide Rule." Photo of a Hyde Park High School, Chicago, IL, classroom with article below describing it as a geometry class learning the application of the slide rule to mathematics. Vol. 1, No 4., pp [2-3]: Trigonometry and the Slide Rule. Vol. 1, No 4., pp [4]: Slide Rule Clubs.