| Year | 1919 |
| Date | 13-Feb |
| Volume | 40 |
| Issue | 929 |
| Page | 100 |
| Category | Electrical |
| Part | |
| Title | Electric Motor Faults and How to Find Them |
| Author | "Calculus" |
| Notes | Some causes of sparking, method of bedding brushes to commutator, undercutting the mica, brush spacing, loose and broken connections, method of testing armature insulation, & for short circuits, armature faults |