| 摘要 |
A clock scale demonstrator especially useful for teaching children to tell time. Separable hour and minute dials, each having a manually movable hand, enable the instructor to demonstrate and explain hour and minute readings separately. The two dials may be mounted in aligned superposed relationship with each other to demonstrate how the two individual readings are then combined with each other, one of the dials being constructed of a transparent material so that the scale and hand of the second dial can be observed when the two dials are superposed.
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