The Birth of Heracles. To find out more about Alcmena's delivery of Heracles, see this Wikipedia article: link; for information about the image: image source.
This is one of my favorite stories from the ancient world, famously told by Ovid in his Metamorphoses. Hera was not at all happy about Alcmena giving birth to Zeus's child, and she did everything in her power to thwart the birth. Alcmena, though, had a loyal servant who managed to trick the goddess and thus allow Heracles to be born. The infuriated Hera then turned the servant, whose name was Galanthis, into a weasel (who is called "gale" in Greek, γαλῆ).
You can also find more myths and legends for the week of August 19-25 here. For more information and links to the actual javascript code, see the Myths & Legends Widget Reference Page.