7 x 35mm Prism Scope for Sextant (Scope Only) Bridge Log Books British Admiralty Nautical Chart 3986:

British Admiralty Nautical Chart 3986: South China Sea

and critical instruments

The red triangles and the gold arrow form a trident

15 Fire protection

Scale: 3121170

7 x 35mm Prism Scope for Sextant (Scope Only) Bridge Log Books British Admiralty Nautical Chart 3986:This 7x35mm Prism telescope fits Tamaya, Astra IIIB and C. Plath sextants. The increased magnification of this scope allows the sun's diameter to appear larger. It also better defines a distant horizon as seen from a ship, helping the navigator determine the point of tangency of the Sun's limb and the horizon. The most important feature of a scope is the fork (sometimes called a rising piece) which should be exactly perpendicular to the optical axis.