| Year | 1955 |
| Date | 20-Oct |
| Volume | 113 |
| Issue | 2,839 |
| Page | 574 |
| Category | Expert's Workshop |
| Part | |
| Title | Measuring Internal Diameters |
| Author | Duplex |
| Notes | Micrometers - internal and external, careful handling needed, false reading is possible, taper gauges, taper mandrel gauges |