Achilles, the Greek hero, had two horses, Xanthus and Balius, which were the offspring of Zephyrus, a wind god. Homer 'Iliad', XVI, 146. The wind god, top right, is probably intended as a personification of Zephyrus.

Painted in Van Dyck's style of the 1620s, and perhaps executed in the second half of the 17th century or in the early 18th century, this picture is proof that Van Dyck's sketches were sought after and imitated at an early date.