| Year | 1939 |
| Date | 25-May |
| Volume | 80 |
| Issue | 1,985 |
| Page | 599 |
| Category | General |
| Part | |
| Title | A Signal Gun |
| Author | C.H.Mathews |
| Notes | A working model with remote firing control. Side view, view showing muzzle end, the breach end with elevating gear and tangent sights |