| Year | 1915 |
| Date | 03-Jun |
| Volume | 32 |
| Issue | 736 |
| Page | 458 |
| Category | Testing |
| Part | |
| Title | The Micro-Indicator for High-Speed Engines |
| Author | R.E.N. |
| Notes | Diagram of Watt's indicator, indicator link motion, diagram of optical indicator, diagram of micro-indicator, external view of micro-indicator |