Assertion: clock | /r/CreatedBy | putting a light output
Facets:
Source sentences:
text: A clock is made by putting a light output at the bottom of a long pole, a mirror on top of the pole, and an electronic light detector down at the bottom of the pole.
text: A clock is made by putting a light output at the bottom of a long pole, a mirror on top of the pole, and an electronic light detector down at the bottom of the pole.