| Year | 2023 |
| Date | 28-Jul |
| Volume | 231 |
| Issue | 4,722 |
| Page | 194 |
| Category | Steam |
| Part | 5 |
| Title | Radial Valve Gears Again |
| Author | Duncan Webster |
| Notes | Hackworth Valve Gear. Sheds light on what is often seen as a complex subject. Layout, Edward Thomas (photo by Peter Broster), connecting rod error, asymmetry in die block travel, valve travel vs. piston travel - straight slide, piston travel - curved slide, design, slide design, references |