The earliest weapons of mass destruction

The ancients developed terrifying devices - and debated whether to use them

After the mythic Greek hero Hercules slew the multiheaded Hydra, he developed a technology at the heart of today's most pressing international crisis. In her illuminating history of warfare, Adrienne Mayor argues that "by steeping his arrows in the monster's venom, Hercules created the first biological weapon."

Mayor, a folklorist specializing in the early history of science, is intrigued with the often fantastic devices the ancients used in war, but "Greek Fire" also excavates ancient attitudes toward biological and chemical arms that are startlingly relevant today.

Toxic arrows were the Bronze Age's terror weapons. "Almost as soon as they were created," Mayor writes, "poison weapons set in motion a relentless train of tragedies for Hercules and the Greeks - not to mention the Greeks' enemies, the Trojans."

Most of the ancient world liked to believe it fought with a code of honor. According to Homer, "Archers were disdained because they shot safely from afar: long range missiles implied unwillingness to face the enemy at close range. And long range missiles daubed with poisons seemed even more cowardly." Yet Odysseus, hardly a coward, returns home to kill his wife's suitors with poison arrows.

Here's the rub that still bedevils us. The rulers of ancient India were no less conflicted than the Greeks about arrows "barbed, poisoned or blazing with flame." These instruments violated the "traditional Hindu laws of conduct for Brahmans and high castes, the Laws of Manu." But in the Arthashastra, the Brahman military strategist Kautilya advised his king to use whatever means necessary to attain his military goals - including poisons.

Mayor is comprehensive about the history, ethics, and science of early biological and chemical weapons. Skillfully combing ancient texts, she describes cultures as varied as the Scythians and the Chinese with their chemical fire lances and poison "vapors." Mayor shows most cultures devised exotic weaponry - and debated their use.

Arrows and flamethrowers were battlefield weapons, but the ancient world also contained examples of biological warfare against general populations stretching back to 1500 BC when the Hittites sent plague victims into the lands of their enemies. The ancient world made an important distinction between using disease weapons for purely defensive purposes as opposed to "first strikes." While this constraint was rooted partially in ethics, Mayor argues it also reflected a shrewd understanding of epidemiology: "The principle of summoning plague for self-defense may be related to the reality that invaders are 'immunologically naïve' and therefore more vulnerable to epidemic diseases in foreign lands than the local population."

While the ancient world's arsenal of biological and chemical weapons was trivial compared with the horrors of the modern world, those weapons raised the same terrifying moral and political dilemmas then as now. Is a bunker-buster bomb dropped from the sky more civilized than a clay pot filled with scorpions thrown into an enemy's cave?

Mayor quotes a king in Asia Minor of the 2nd century BC who was defeated when Hannibal "catapulted live snakes onto his ships." The king remarked that "he did not think any general would want to obtain a victory by the use of means which might in turn be directed against himself."

• Jay Currie is a freelance writer in Vancouver.