| Year | 1944 |
| Date | 10-Aug |
| Volume | 91 |
| Issue | 2,257 |
| Page | 129 |
| Category | Internal Combustion |
| Part | |
| Title | Experiments in Four-stroke Engine Design. A review of several years' efforts to improve the breed of model petrol engines for speed-boat propulsion and other purposes |
| Author | Edgar T.Westbury |
| Notes | General arrangement of "Apex II" 30 c.c. engine, worm-geared metering oil pump, timing diagram, the "Apex" engines, identification justified, the "Apex I" 30 c.c. engine, lost power explained, "Apex Minor" |