| Year | 1941 |
| Date | 22-May |
| Volume | 84 |
| Issue | 2,089 |
| Page | 416 |
| Category | Inventions. Successful and Otherwise |
| Part | 6 |
| Title | A Triple-acting Air-cleaner |
| Author | B.C.J. |
| Notes | Path of dust particle under influence of centrifugal force, with addition of dust trap, with the addition of bye-pass dust trap, a portion of an experimental air-cleaner, view of commercial air-cleaner |