No. 1 Principles of the Layout of Signals. The specific editions are shown in one of the scans. No. 2 Principles of Interlocking.
VINTAGE BRITISH RAILWAY SIGNALLING LAMP & BURNER Stamped BR RARE GLASS TYPE
BRITISH RAILWAY SIGNALLING EVOLUTION DURING 19th 20th & EARLY 21st CENTURY BOOK
BRITISH RAILWAY SIGNALLING & ASSOCIATED TRACK PLANS DURING 20th CENTURY BOOK
BRITISH RAILWAY SIGNALLING EVOLUTION DURING 19th & 20th CENTURY BOOK
