From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Diagram showing the Essex arrangement of a hot spot with winter and summer positions.
| Identifier | ExFiles\Box 21\6\ Scan103 | |
| Date | 27th October 1933 | |
| ESSEX ARRANGEMENT OF HOT SPOT SHEWING WINTER AND SUMMER POSITIONS DOTTED SECTION BEING SUMMER INLET PASSAGE 1.7" 1.8" EXHAUST GASES FROM THE REAR FOUR CYLINDERS FLOW ROUND THE INLET PASSAGE WHEN HOT SPOT CONTROL IS IN THE 'WINTER POSITION' ROLLS-ROYCE, LTD. PRINT ROOM OCT 27 1933 DERBY. | ||