Block instrument (sending/receiving)
Single-needle block instrument
1845
Clark's block signalling telegraph instrument, 1854
1854
Block instrument (sending)
Block instrument (sending/receiving)
Block instrument (lock and block)
1897
Block instrument
Two-plunger block instrument pattern 288
Block instrument (permissive indicating)
Block instrument (sending/receiving)
Intermediate block instrument
Telegraph block instrument, old form of bell instrument
Telegraph Block Instrument, Lock & Block Type, W R Sykes & Co
Telegraph Block Instrument, Markham North
Telegraph Block Instrument, Lock & Block Type, W R Sykes & Co
Telegraph Block Instrument, Lock & Block Type, W R Sykes & Co
Telegraph Block Instrument, Lock & Block Type, W R Sykes & Co
Lock & Block Type Telegraph Block Instrument
Telegraph block instrument
Telegraph block instrument, London Brighton & South Coast Railway
London & North Eastern Railway train describer
1923-1948
BR block instrument
1912
Single-needle telegraph block instrument
Three-wire block instrument
Telegraph block instrument
Telegraph block instrument
Block instrument with spagnoletti flag indicator (incomplete); GWR. Tyer's style
Telegraph Block Instrument, Signal Relay, Great Western Rail
Telegraph Block Instrument, Spagnoletti type
Telegraph Block Instrument, Great Western Railway Spagnoletti receiving type
Telegraph Block Instrument, Great Western Railway
Train describer (receiving)
Train describer (receiving) Great Western Railway
Tyer's One-Wire Three Indication Block Instrument
Block instrument, Great Central Railway (sending)
Telegraph Block Instrument; Tyers Patent; 2-position type
Wooden shelf with black-painted metal brackets
Ringing Key for Tyers Block Instrument
Siemens Bros. block
Lock and Block Type Block Instrument
Telegraph Block Instrument, Lock & Block Type, W R Sykes & Co
Telegraph Block Instrument, Lock & Block Type, W R Sykes & Co
Telegraph Block Instrument, Lock & Block Type, W R Sykes & Co
Telegraph Block Instrument, Lock & Block Type, W R Sykes & Co
Telegraph Block Instrument, Lock & Block Type, W R Sykes & Co
Block instrument by J.R. Spagnoletti and Crooks; GNR
Tyers Type Signalling Block Instrument
Block instrument (sending/receiving)
