| Year | 1916 |
| Date | 27-Apr |
| Volume | 34 |
| Issue | 783 |
| Page | 292 |
| Category | Electrical |
| Part | 1 |
| Title | The Principles of Modern Printing Telegraphy |
| Author | H.H.Harrison |
| Notes | Elements of installation, using polarized receivers & double-current transmitting keys, using line wires equal to the number of characters, using polarized selective means, principle of permutation, step-by-step type printing |