| Year | 1904 |
| Date | 11-Aug |
| Volume | 11 |
| Issue | 172 |
| Page | 139 |
| Category | Correction |
| Part | |
| Title | The Construction of Model Alternators |
| Author | "Zodiac" |
| Notes | Magnetisation of iron, law of the magnetic circuit, magneto-motive force, magnetic flux, ampere turns per unit length, magnetic leakage |