| Year | 1928 |
| Date | 22-Mar |
| Volume | 58 |
| Issue | 1,402 |
| Page | 272 |
| Category | Electrical |
| Part | 3 |
| Title | Practical Private Telephone Installations at Low Cost |
| Author | B.Clements Henry |
| Notes | Switch Gears. The same (choke-fault type), "metallic circuit" or double-line switch, commutator-push (new system), details, a new device |