| Year | 1915 |
| Date | 18-Feb |
| Volume | 32 |
| Issue | 721 |
| Page | 136 |
| Category | Electrical |
| Part | |
| Title | A 20-Cell Electro-Medical Constant-Current Battery |
| Author | G.Gentry |
| Notes | Cross section of case, switchboard clamp, detail of commutator, detail of bolt for small case, showing position of carrying case for galvo. fittings, sketch explaining principle of commutator, crossover switch |