I find militaria all over the place; online, in charity shops and on the market, tonight’s object however is the first one to have stabbed me in the process! I was rooting around in a box, felt a sharp pain in my finger and realised I had stabbed myself on something. On closer inspection the offending object was a lovely pair of Air ministry marked navigation dividers:These dividers were used to measure distances on a map. The points would be set to the correct distance for say 1 mile by using the scale on the bottom of the map; then by twisting the compass form point to point an accurate estimation of distance can be made. The dividers are adjusted by using a knurled metal knob on a screw thread on the side of the instrument:The arms of the divider are kept under permanent tension by a large spring at the top:The dividers are marked with a crown and ‘AM’ mark for the air ministry, and a date of 1937:The manufacturer of these dividers is ‘Moore and Wright Ltd’ of Sheffield:This company must have been a regular supplier to the RAF as I have found another contract for dividers, placed in October 1938 so the Air ministry was clearly fairly happy with the instruments they received. Moore and Wright were founded in 1906 and by the 1930s produced a wide range of precision measuring instruments, this advert dating from 1933:The company finally went out of business in 1970.
Dividers were an essential tool in navigating a plane and were one of many items in a navigator’s kit bag:
Navigator’s Log Book F441. Douglas Protractor 6B/47. Cpt. Field’s Parallel Rule. Course & Speed Calculator 6B/125 or similar. Navigation Computer MkIII, various differences for different types of aircraft. Bubble Sextant MkIX, cased. Dividers, Chart. Rules. Pencil sharpener. Rubber. Pencils, Lead. Various grades, soft for use with the Nav Comp, etc. Pencils, chinagraph. Charts. GEE Lattice Chart, if suitable. Star Plotter Projector sheets. Wristwatch MkVII 6B/159 or MkVIII 6B/234. Stopwatch MkIII, MkV, 6E/287 or 6B/221.