| Year | 1970 |
| Date | 04-Dec |
| Volume | 136 |
| Issue | 3,406 |
| Page | 1,169 |
| Category | Locomotive |
| Part | 9 |
| Title | Princess of Wales. 5 in. gauge Midland Railway 4-2-2 "Single" |
| Author | Martin Evans |
| Notes | Simplex boiler design and stay testing, strengths of firebox stays under bending stress, Princess valve gear, stuffing boxes |