Mighty as Hercules was, he sometimes prevailed only by means other than his own brute strength. When the need arose, the superhero of Greek mythology armed himself with biochemical weaponry, anticipating the technological innovations of modern warfare.
Up against the Many-Headed Hydra, Hercules forced the monstrous serpent from its den by shooting fiery arrows coated with pitch. After finally slaying the Hydra, he cut open the body and dipped his arrows in its poisonous venom. His quiver was never again without a supply of poison arrows.
The story of Hercules and the Hydra may be the first description in Western literature of chemical and biological weapons. Because myth often contains a kernel of historical reality, the story suggests that projectiles tipped with combustible or toxic substances must have been known early in Greek history, and widely used in combat.
It may hardly be a coincidence, for example, that the word ''toxic'' is derived from the ancient Greek word ''toxon,'' meaning arrow.
In a new book praised as an illuminating revision of early military history, Adrienne Mayor marshals not just myth, but also the writing of ancient authors and evidence from archaeological digs to show that biological and chemical weapons saw action in battles long before the modern era of mustard gas, napalm and a Pandora's box of pathogens.
The Greeks of antiquity were not the only ones to weaponize nature. Ms. Mayor cited evidence of biological agents in ancient battles from Europe and the Mideast to India and China. Among the historical victims and perpetrators were conquerors like Hannibal, Julius Caesar and Alexander the Great.
''The sheer number of legendary narratives and historically verifiable incidents,'' Ms. Mayor concluded, ''invites us to revise assumptions about the origins of biological and chemical warfare and its moral and technological constraints.''
Ms. Mayor is an independent scholar of the classics and folklore who lives in Princeton, N.J. Her book, recently published by Overlook Duckworth, is ''Greek Fire, Poison Arrows and Scorpion Bombs: Biological and Chemical Warfare in the Ancient World.''
Robert Cowley, a founder and former editor of MHQ: Quarterly Journal of Military History, said last week that the book was ''a solid contribution to military history.'' Ms. Mayor, he added, has ''done something no one's done before, bringing together all this material on the dirty tricks of ancient warfare, and think how relevant it is with our present obsession with weapons of mass destruction.''
The book also is issued at a time of resurgence in scholarly interest in the origins and history of war. Historians and archaeologists are paying increasing attention to overlooked evidence of warfare among tribal societies and chiefdoms, as well as advanced civilizations.
The Maya, once thought to be a peaceful culture ruled by priests more devoted to calendars than hostilities, have now been found to have had plenty of blood on their hands. On Tahiti, where the people were considered avatars of Rousseau's Noble Savage, war was frequently brutal and merciless. Nearly all premodern societies, some scholars find, often decimated their numbers in violent warfare.
''People have finally realized that scholars and others have been denying reality,'' Dr. Steven A. LeBlanc, director of collections at the Peabody Museum of Archaeology and Ethnology at Harvard, said last week. ''War is universal and goes back deep into human history.''
Dr. LeBlanc is the author of ''Constant Battles: The Myth of the Peaceful, Noble Savage,'' written with Katherine E. Register and published this year by St. Martin's Press. He credits Dr. Lawrence H. Keeley, an anthropologist at the University of Illinois at Chicago who published ''War Before Civilization'' in 1996, with broadening understanding of warfare across time and cultures.
Dr. LeBlanc has not read Ms. Mayor's book, but he said he suspected that, if anything, she had not explored biochemical warfare far enough back in time. Although she cites Sumerian cuneiform tablets relating to knowledge of deadly pathogens in 1770 B.C., her book concentrates on warfare beginning in the Greek and Roman eras, when documentation is more reliable.
Ms. Mayor turned her expertise in mixing mythology, archaeology and history toward biochemical weapons after the Sept. 11, 2001, terrorist attacks. ''After the anthrax scare, especially,'' she said in an interview, ''I knew how timely a history of biochemical warfare was.''
Classics scholars, Ms. Mayor said, advised her that the Greeks would never have used toxic weapons because of their sense of the ''fair fight.'' Other writers seldom investigated biochemical warfare in earlier history, in part because it was assumed to be a recent innovation, little older than the gas attacks of World War I. The ability to manipulate pathogens, toxins and chemicals as agents of war surely required modern knowledge of epidemiology, biology and chemistry. Only a few well poisonings or the catapulting of a plague victim over an enemy wall passed for biochemical combat in antiquity, or so it was thought.