| Year | 1920 |
| Date | 18-Mar |
| Volume | 42 |
| Issue | 986 |
| Page | 268 |
| Category | Workshop |
| Part | 1 |
| Title | Small Power Machine Shop Calculations |
| Author | Hubert Bentley |
| Notes | Two-speed Countershafts, countershaft arrangement for driving 6" & 8" lathes, alternative arrangement, cone-driven headstocks, common type of fast headstock, duplex gear headstock, all-gear headstocks, four-speed & 16 speed all gear headstocks |