ANDRONICUS OF CYRRHUS, Greek astronomer, flourished about
100 B.C. He built a horologium at Athens, the so-called
Tower of the Winds, a considerable portion of which still
exists. It is octagonal, with figures carved on each side,
representing the eight principal winds. In antiquity a bronze figure of
Triton on the summit, with a rod in his hand, turned round by the wind, pointed to the quarter from which it blew. From this model is derived the custom of placing weathercocks on steeples.
Initial text from 1911 encyclopedia -- Please update as needed