Silver boatswain's call from the Royal Naval College Osborne.

The call has a plain spherical buoy and a plain keel engraved with a naval crown and inscribed 'R.N.C.O.'. A rope lanyard is attached to the ring (shackle).

The boatswain's call has a long history both as a symbol of office and as a practical instrument for conveying orders at sea. Its distinctive shape has remained practically unchanged from medieval times to the present day. The call's shrill whistle can be varied in pitch to convey a variety of information, and can be heard above the sound of wind and sea. Such instruments were private possessions rather than official equipment and silver calls like this one made suitable gifts and presentation pieces.

Royal Naval College Osborne opened in 1903 at Osborne House, East Cowes, Isle of Wight, as a training college for junior officers. It closed in 1921 and the last students left on 9 April 1921.

Osborne House, Queen Victoria’s former residence, is now open to the public (English Heritage).