| Year | 1924 |
| Date | 03-Jul |
| Volume | 51 |
| Issue | 1,210 |
| Page | 15 |
| Category | Electrical |
| Part | 3 |
| Title | The "C.-H." Electrical Locks |
| Author | B.Clements-Henry |
| Notes | Pin-hole contact, grooved mouldings for enclosing wires, grooved-in wires, three methods of wiring door lock, door wiring, scratch too and cutters to form grooving |