| Year | 1923 |
| Date | 31-May |
| Volume | 48 |
| Issue | 1,153 |
| Page | 569 |
| Category | Testing |
| Part | |
| Title | The Edward Herbert "Pendulum" Hardness Tester |
| Author | |
| Notes | Testing hardness of a milling cutter, hardness tester and some accessories, curves of results of test by the "pendulum" instrument, taking the instrument to the job |