This protractor is 6 1/8 inches in diameter, nickel-plated brass, and in immaculate condition. It is in its original mahogany velvet-lined box. The full 360 degree scale is graduated to one half of a degree.
The firm of Elliott Brothers produced a wide range of instruments over many years. The founder, William Elliott, began practice in about 1795 and was joined by his sons Frederick and Charles in the 1840s. They absorbed Watkins and Hill in 1857 and advertised as Opticians to the Admiralty.
Instruments signed "Elliott Brothers", as this one is, are generally 1850 and later. Elliott Brothers was still in existence in the mid-20th century.
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