Two Roman gods and a goddess, accompanied by a Victory, peer down from the edge of a bank of clouds. On the left, holding a large key, is Janus, the guardian of the doorways of houses and city gates. He is traditionally portrayed with two faces, demonstrating his ability to look both ways at once. In the center, the bearded figure of Chronos personifies Time. In one hand he holds a scythe, while a snake gripping its tail in its mouth wraps itself around his neck. Such a snake holding its tail was an ancient Egyptian symbol of eternity. Gaea, the goddess of the Earth, crouches at Chronos's feet with another snake grasped in her right hand. The winged figure of Victory, her hair streaming out to the side, stands behind these three and holds out a crown in her left hand.
Giulio Romano made this drawing in preparation for part of the frescoed vault of the Sala dei Giganti (Room of the Giants) in the Palazzo del Te, the summer residence of the court of Giulio's patron, Federico Gonzaga, duke of Mantua. Giulio completed the preparatory drawings for the fresco, and his assistants then squared them for transfer to the ceiling.