“WAAF”

Data:

• During World War II, British Women's Auxiliary Air Force (WAAF) personnel used large cicular slide rules to calculate bomber routes, undertake meteorological forecasting, and plot aircraft positions. (Source: Computer History Museum)
  A similar device was used by ATS (Britisch Army Auxiliary Territorial Service) for calculating A.A. (Anti-Aircraft) Gunfire Accuracy using a kine-theodolite, a film evaluator and a slide rule. photo 1 and photo 2. Andries de Man
  “The ATS girls are good draughtswomen are useful for making slide rules and other A.A. equipment for experiments” (annotation on photo of Pte. Kathleen Lavery designing a special plotter). Jose Fernández
  You can see the device in action in the video “Girls Work Kine-Theodolite” (at 61 seconds)
  More on the kine-theodolite, auxillary instruments and calculations: cdvandt.org Andries de Man
  

Questions:

1. Who manufactured this slide rule?
   There is currently (October 2026) one for sale in Norway!
   From the seller's description:
   In typical military fashion it is called a “Rule, Slide, Kine-Theod[oli]te, Mk. 1” and is also marked “Reliance, Twickenham, 1940 Regd. No. 30” Andries de Man
   Graces Guide mentions Reliance Nameplates Ltd, Richmond Bridge works, Cambridge Road, Twickenham as a manufacturer of nameplates and dials.
   Is this the manufacturer?
   Straight Reliance slide rules are known, e.g. from the collections of David Rance, Tina Cordon and John Mosand, with just the word “Reliance” and a helmeted head (Minerva?) logo.
   David's and Tina's slide rules also show the UK government broad arrow mark. Andries de Man
   The 1974 edition of “Kelly's Post Office London Directory”, pages 1331, 1731, 2025 mentions Reliance Nameplates Ltd., Richmond Bridge Works, Twickenham, Middx, in the sections “Dial manufacturers”, “Nameplate engravers — ivorine”, “Nameplate engravers — metal.”
   Note the advertisement does not show the helmeted head logo. Andries de Man
   The company started as March 7, 1910 as “The Sound Recording Company, Limited”
   In 1923 changed to “Associated Ivorine & Metal Products Limited”
   In 1930 changed to “Reliance (Nameplates) Limited”
   In 1962 changed to “Reliance Nameplates Limited”
   In 1982 changed to “Reliance Compra Limited” (industrial nameplates, clock dials, decorating metal and plastic trims and instrument dials for the car and other industries)
   In 1989 changed to “Hall Industries Ltd”.
   Source: Hall Industries Ltd company profile, esp. 18 Oct 1988 Memorandum and Articles of Association Andries de Man
   Note that a 1929 letterhead states that “Associated Ivorine & Metal Products Limited” was an association of “Ivorine Ltd”, “The Reliance Engraving Co. (1904) Ltd.” and the “Endolithic Manufacturing Co. Ltd.” The 1918 Directory of Manufacturers in Engineering and Allied Trades, page 562 locates “The Reliance Engraving Co. (1904) Ltd.” at Waldeck Road, Chiswick, London; having 24 male, and 20 female employees. Its pre-war (i.e. World War I) work is listed as “Engineers and general press metal engravers. Founders. Light and heavy stampers. Press tool makers. Advertising novelties and metal small wares.” while its war work was “Cast, stamped, engraved and radiumized work in all metals, celluloid, fibre, &c., aircraft instruction plates, and as pre-war” Andries de Man
   
2. What scales are on it?
   Inner ring: Base Angle.
   Middle ring: Apex Angle, Angle of Sight.
   Outer ring: Height Feet, Base Yards (partial scale).
   Andries de Man
3. How does the cursor work?
   See Summary: Slide Rule Disc for Kinetheodolite Jose Fernández