| Year | 1920 |
| Date | 08-Jul |
| Volume | 43 |
| Issue | 1,002 |
| Page | 29 |
| Category | Railway |
| Part | |
| Title | Railway Signalling Systems |
| Author | |
| Notes | Chapter 2. - Lighting of Signals. Interior for signal lamp, electric light lamp holder, view of locking frame, interior of a signal box, Chapter 3. - Locking Frames. Diagram of interlocking, diagram of lines |