A rare Barker military night marching 'Mica Dial' compass, dating from c.1877. This particular design features a very unusual transparent mica compass card. The mica is totally transparent and very thin, with a hand-painted compass rose, triangular black North marker and circular South marker. The compass has a jewelled pivot, brass hunter case and automatic transit lock. The case would originally have had an oxidised or bronzed finish, and this can still be seen inside the lid. There is also a paper sighting line inside the lid. The sighting line and the paper insert below the mica dial were painted with a luminous compound, most probably an early version of 'Balmain's Luminous Paint', a compound of Calcium Sulphide which was patented by William Balmain in 1877. The paint was made luminous by exposure to sunlight or burning a strip of magnesium ribbon near the compass. The combination of a fully transparent dial and the luminous interior of the case made this type of compass particularly suitable for night marching and military use.
Although there are no maker's marks or retailer's details on the compass, the Mica Dial was a well-known Francis Barker design that first appeared around 1865. Military prismatic compasses of a similar design, such as the 'Major Sawyer's Prismatic and Luminous Compass', were also retailed by J. H. Steward in the 1890's, and these were clearly a development based on the earlier Barker design. Major Sawyer, of the War Office Intelligence department, had approached Steward with his suggestions for a new military compass after his experiences in the Sudan in the 1880's. From the 1890's until around 1905 Steward sold Major Sawyer's prismatic design and also the non-prismatic 'Steward's Military Compass', which shared many of the Mica Dial's design characteristics, but relied on the 1860's Singer's Patent style of compass card for its night marching function.
(Further details of the Barker Mica Dial compass design can be found at Paul Crespel's excellent trademarklondon.com website, and in his book Trade Mark London p.101)
Francis Barker & Son: were established in London in 1848, as a maker of compasses and scientific instruments. Francis Barker produced a very wide range of compass designs over the years, supplying major retailers such as Negretti & Zambra, J. Lizars, C. W. Dixey, Dollond, and many others. The company prospered until 1932, when it was taken over and became F. Barker & Son (1932). After WW2 the company changed hands several times and Barker compasses are now manufactured by Pyser Optics at Edenbridge in Kent. They continue to produce the renowned Barker M-73, widely acknowledged to be the world's finest prismatic compass.
The compass is in very good condition, full working order, and finds North well. There is some minor wear to the brass case. The lid closes very well, and the hinge is strong. The mica compass card is in very good condition.