| Year | 1979 |
| Date | 02-Mar |
| Volume | 145 |
| Issue | 3,604 |
| Page | 292 |
| Category | Nautical |
| Part | |
| Title | The Early History of the Screw Propeller |
| Author | Vic Smeed |
| Notes | George Hunt's steerable screw, George Rennie 1839 patent, contra-rotating design by David Napier in 1841, Robert Walker Jnr. 1843. "Archimedes" |