| 968 / | HD | HOROLOGY |
| 524 | DD | DRIVING MECHANISMS FOR CLOCKS BY MASTER CLOCKS [G04C 13/00] {2} |
| 525 | DD | .~ Circuit arrangements; electric clock installations [G04C 13/02] {5} |
| 534 | DD | .~.~ Master clocks [G04C 13/04] {4} |
| 545 | DD | .~.~.~ Contact devices (for simultaneously winding several clocks subclass 426) [G04C 13/06] {1} |
| 546 | | .~.~.~.~ Controlled by a pendulum or a balance [G04C 13/06B] |