| Year | 1954 |
| Date | 13-May |
| Volume | 110 |
| Issue | 2,764 |
| Page | 518 |
| Category | More Utility Steam Engines |
| Part | |
| Title | Boiler Design and Construction |
| Author | Edgar T.Westbury |
| Notes | Centre-flue boiler by the Imperia Co., the "Trident Mark I" boiler, end views and sectional elevations (of the Trident Marks I and II boilers), evolution of boiler design, components |