| Year | 1934 |
| Date | 29-Nov |
| Volume | 71 |
| Issue | 1,751 |
| Page | 525 |
| Category | Electrical |
| Part | |
| Title | Electrical Installation Work |
| Author | Cyril Sylvester |
| Notes | Solutions to Problems set by the City and Guilds of London Institute at the 1934 Technological Examinations. Relay circuit operating a fire bell of large capacity |