Catapult Makers: Rock Stars of Antiquity

Brian Handwerk
for National Geographic News
February 5, 2004
Ancient catapults were state-of-the-art weapons of unequalled power—but how powerful were the military engineers who created them?

"Both the engineers and their achievements were an important part of ancient society," writes Serafina Cuomo, of Imperial College London's Centre for the History of Science. "In antiquity," she added, "catapults not only changed the art of war, but also inaugurated a new era in the relations between political power and technical experts."

Cuomo's recent interpretation, entitled The Sinews of War: Ancient Catapults, is published in the February 6 issue of the journal Science.

Science on the Ancient Battlefield

The making of catapults, known as "belopoietics" (poietike meaning "making of"; belos meaning "projectile or projectile-throwing device") required an ingenious combination of geometry, physics, and technology.

The fearsome machines terrorized battlefields and sieges until the proliferation of gunpowder. Their power was impressive and terrifying. Roman catapults could hurl 60-pound (27-kilogram) boulders some 500 feet (150 meters). Archimedes' machines were said to have been able to throw stones three times as heavy.

The origins of the catapult are unknown. They appear in the historical record as early as a 9th-century B.C. relief from Nimrud in modern-day Iraq.

Early Greek catapults were large bows that included winches able to draw the weapon for firing.

At some point, possibly under Phillip II of Macedonia (382-336 B.C.), father of Alexander the Great, bow arms were replaced by tight bundles of sinew or rope which functioned as "springs."

By the 4th century B.C. catapults were quickly becoming popular throughout the Mediterranean. That technological creep may have stemmed from events like those depicted in a popular ancient story of Dionysius—ruler of the Sicilian city of Syracuse.

In 399 B.C., according to the account of Diodorus of Sicily, Dionysius gathered craftsmen from all the cities in his domain. Motivating them with high wages, gifts, and personal praise, he spurred them to construct great numbers and types of weapons. Cuomo describes the strategy as "an inspiring example of policy-driven research."

But was that gathering of top technical minds really responsible for increasing and dispersing knowledge of catapult-building?

Jonathan Roth, an ancient military historian at San Jose State University, finds the idea interesting.

"The catapult is one of the few cases where we think we know something about how ancient technology developed," he said. "It depends what you think of the story of Dionysius and Syracuse.

"The story is interesting and a rare example from antiquity, but we don't really know very much about it. It does seem that torsion artillery, like the catapult, developed at some point and then spread very rapidly. So that kind of story makes some sense in light of what happened. But we just don't know much about these events or people—not even about Archimedes."

Archimedes, the legendary mathematician and philosopher, is regarded as one of the ancient world's most prominent military engineers. He's credited with staving off the Roman siege of Syracuse through his ingenious construction and employment of war machinery.

"Archimedes is somebody who might have been very much like the people that Dionysius is said to have brought together," Roth said. "But even though we know much more about him than about almost anyone else whom you might call a type of ancient 'military engineer,' we know virtually nothing about Archimedes. What was his relationship to the state? How did that work? It's very hard to say."

Roth also maintains that much can still be learned on the subject from the types of historical sources examined by Cuomo.

"I do think that there is a tendency to be too critical of the sources and say that ancient people didn't have the concept of thinking about techniques of war in a sophisticated way," he said. "But it does make some sense that the people involved in warfare, which was very significant in the ancient world, knew what their technical problems were and actively looked for solutions to them."

Standards and Subsidies

Cuomo believes that those problems were increasingly addressed by the application of organized scientific knowledge.

Through long experience the ancients identified a basic principle of catapult construction. It stated that all parts of the machine, including the stone or projectile, were proportional to the size of the torsion springs. The establishment of this principle had a dramatic effect.

"Whereas in the old days of trial-and-error, results could never be guaranteed, the introduction of proportionality and thus mathematics allowed catapult construction to be almost standardized," Cuomo writes in Science. "Tables of specification were compiled for quick and easy reference."

Philo of Byzantium (ca. 200 B.C.), in his Belopoietics, promoted using such knowledge for machines that fired long-distance shots, describing such range as something "which they display the greatest enthusiasm over and would exchange anything for." The "they" in Philo's reference is unclear, but Cuomo suggests that it may have been the powerful political figures of the day. Philo goes on to say that technicians in Alexandria were heavily subsidized by ambitious kings who fostered craftsmanship.

Cuomo believes that other governments were not only interested in belopoietics, but financially supportive of the science. "By the end of the 4th century B.C., any state with political aspirations needed a semiprofessional army, any army required machines, and any city had to have a fortified wall," Cuomo writes.

"The rise of advanced catapults, better fortifications, and manuals on artillery and tactics was accompanied by a rise in the visibility and status of engineers, who also worked as architects and surveyors," she says.

In fact, as early as the first century A.D. technology had evolved so far that at least some felt little further improvement was possible. Cuomo cites the Roman Sextus Julius Frontinus' belief that "The invention of [machines of war] has long ago been completed and I don't seen anything surpassing the state of the art."

Technology, of course, has since evolved by leaps and bounds.

"The technologies [the engineers] boasted of may now be obsolete, but their anxieties, their curiosity, and their pride in their knowledge are not—perhaps the people behind the machine have not changed that much," says Cuomo.

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