Andron īcus in Harpers Dictionary of Classical Antiquities

Cyrrhestes, an astronomer of Athens, who erected, B.C. 159, an octagonal marble tower in that city to the eight winds, now known as the "Tower of the Winds." On every side of the octagon he caused to be wrought a figure in relievo, representing the wind which blew Tower of the Winds. against that side. The top of the tower was finished with a conical marble, on which he placed a brazen Triton, holding a wand in his right hand. This Triton was so contrived that he turned round with the wind, and always stopped when he directly faced it, pointing with his wand over the figure of the wind at that time blowing. Within the structure was a water-clock, supplied from the fountain in a turret. Beneath the eight figures of the winds lines were traced on the walls of the tower, which, by the shadows cast upon them by styles fixed above, indicated the hour of the day, as the Triton's wand did the quarter of the wind. When the sun did not shine recourse was had to the water-clock within the tower, which building thus supplied both a vane and a chronometer. The structure still stands, though in a damaged state. To the correctness of the sundials Delambre bears testimony, and he describes the series as "the most curious existing monument of the practical gnomonics of antiquity." There are two entrances, facing respectively to the northeast and northwest; each of these openings has a portico supported by two columns. (See Vitruv. i. 6, 4.)

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