Hydra

Hydra, in Greek legend, a gigantic, many-headed, serpentlike monster that inhabited the marshes of Lerna, near Árgos, in southern Greece. The Hydra was particularly difficult to kill because two new heads would grow whenever one was severed. Its destruction became the second of the 12 Labours of the Greek hero Heracles (Hercules).

Origins and characteristics

According to the early Greek poet Hesiod’s Theogony, the Hydra was the offspring of Typhon and Echidna, two monstrous figures in Greek mythology. Hera, the wife of Zeus, raised the creature to one day destroy Heracles, who was Zeus’s son by the mortal Alcmene. The Hydra lived near the spring of Amymone in the marshes of Lerna, from which it emerged intermittently to threaten livestock and devastate the surrounding countryside.

The number of the Hydra’s heads varies among ancient accounts. In the Bibliotheca, attributed to the mythographer Apollodorus, the monster had nine heads, one of which was immortal. The historian Diodorus Siculus, however, describes a creature with 100 heads. The traveler Pausanias questioned whether the Hydra had multiple heads at all. He suggested that it had originally been described as an enormous water snake with a single head and credited the poet Peisander with introducing its many-headed appearance.

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From Athena to Zeus: Basics of Greek Mythology

Heracles and the Hydra: The second labour

The destruction of the Lernaean Hydra became one of the 12 Labours of Heracles. For that and other labours, Heracles enlisted the aid of his nephew Iolaus. As Heracles severed each mortal head, Iolaus was set to the task of cauterizing the fresh wounds so that no new heads would emerge. To help the Hydra an enormous crab attacked Heracles, biting his foot. When only the immortal head remained, Heracles cut it off too and buried it under a heavy rock. Further, he dipped his arrows in the beast’s poisonous blood (or venom) to be able to inflict fatal wounds. The poison later contributed to Heracles’ death.

The Hydra’s poison and the death of Heracles

Heracles used one of the poisoned arrows to kill Nessus, a centaur who had attempted to assault Heracles’ wife, Deianeira. The wound contaminated Nessus’s blood with the Hydra’s poison. Before dying Nessus deceived Deianeira into believing that the blood from his wound could help her remain the sole object of her husband’s affections. Later, fearing that Heracles had fallen in love with a woman named Iole, Deianeira applied the blood to a garment and sent it to him. The poison caused Heracles terrible suffering. In Ovid’s Metamorphoses heat causes the poison in the garment to penetrate Heracles’ body. The cloth clings to him, and when he tries to tear it away, it pulls away his skin and flesh. Thus, the poison Heracles had taken from the Hydra ultimately brought about his death.

The episode is recounted in Sophocles’ tragedy Trachinian Women, in which Deianeira unintentionally brings about her husband’s destruction.

The Hydra in ancient art and later culture

The battle between Heracles and the Hydra was a subject of ancient art. The Caeretan Hydria, a painted water jar made in Etruria, in central Italy, about 520–510 bce, depicts Heracles confronting the monster with the help of Iolaus. The scene also shows Iolaus about to strike one of the Hydra’s heads using a sickle, with a fire beneath him. It also depicts the giant crab that attacked Heracles. The vessel is now in the Getty Museum.

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The Hydra’s multiplying heads also became a metaphor for problems that grow more complicated as people attempt to resolve them. In Plato’s dialogue Euthydemus, Socrates compares a difficult argument to Heracles’ struggle with the monster. In modern English hydra or hydra-headed can describe a difficult or multifarious situation. The name Hydra has been assigned to a genus of invertebrate freshwater animals having a circlet of 4 to 25 tentacles on one end of their tubelike bodies.