| 968 / | HD | HOROLOGY |
| 564 | DD | INDICATING THE TIME OPTICALLY BY ELECTRIC MEANS (subclass 577 takes precedence; by mechanical means subclasses 139 and 162) [G04C 17/00] precedence; by mechanical means subclasses 139 and 162) [G04C 17/00] {6} |
| 570 | DD | .~ By discs (by drums subclass 573) [G04C 17/00S] {1} |
| 571 | DD | .~.~ With date indication [G04C 17/00S2] {1} |
| 572 | | .~.~.~ Electromagnetically driven, e.g., intermittently, etc. (clocks incorporating stepping motor subclass 490) [G04C 17/00S2B] |