Telegraph block instrument, Preece's type

Telegraph block instrument; block section release with combined bell; Preece's type. Absolute single-semaphore (lower-quadrant/red with white spot) block-indicator 2-position / 2-indication ("Line Blocked"/"Line Clear"), mounted on a vertical brass-finialled post in a large rectangular brass bezel. Above this is a dynatape-label "No 2 Road Up Ascot A" and below is an ivorine plate "No 2 Road Ascot A". The blanked-off semicircular bezel hides redundant signal-information, while above, in the recessed top of the instrument, is a blockbell-dome with striker.