| Year | 1926 |
| Date | 18-Mar |
| Volume | 54 |
| Issue | 1,299 |
| Page | 307 |
| Category | Light Engineering Equipment and Supplies |
| Part | |
| Title | The "Compacto" Electrolytic Rectifiers (Walsh & Calverley) |
| Author | |
| Notes | Different readings by directional and non-directional ammeters in series, electrodes of rectifying cell |