Block instrument (sending/receiving) - Caledonian Railway

Block instrument; Caledonian Railway. Tyer's 2-needle (Up/Down Line) F-Type 3-position absolute pegging/non-pegging instrument (with internal bell). Has circular, electroplated/brass line-description plate ("Greenhill Lower"), bakelite-wedge commutator, electroplated bell-plunger (bottom/RHS), and bakelite release-button in circular aperture (middle/RHS).

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National Railway Museum: Warehouse

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Related people


Signalling & Telecommunications
Object Number:
block instrument
British Rail, Clapham

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