The Three-span Arrow Projector is useful for providing a covering-fire on enemy walls, or firing at hostile missile troops at a greater range than they themselves can reach. A focused barrage from a large enough battery can be particularly devestating on heavily armoured units such as eastern Kataphraktoi / Grivpanvar, while they are still far out of charging distance - often forcing them to attack you first.
The Trispithamos Katapeltes is a torsion-based Three-span Arrow Projector which hail from Greek progeny. This Three-span Arrow Projector is useful for providing a covering-fire on enemy walls, or firing at hostile missile troops at a greater range than they themselves can reach. A focused barrage from a large enough battery can be particularly devestating on heavily armoured units such as eastern Kataphraktoi / Grivpanvar, while they are still far out of charging distance - often forcing them to attack you first.
The first (recorded) Katapeltes was invented in 399 BC at Syrakousai. As the Peloponnesian War approached its dreary conclusion, a new era of Greek siege warfare was beginning in Sicily. The Tyrannos Dionysios of Syrakousai emerged as the first Greek commander to master all the methods of siege warfare. The shocking catastrophe of the Athenian defeat in the siege of Syrakousai had been the great event of his youth and undoubtedly impressed him with the pitfalls of passive siege methods. Four years after the Syrakousioi repulsed the Athenian invasion, Sicily suffered another, much more devestating invasion by the Carthaginians, a Phoenician people who knew eastern siege methods. Threatened his entire life by the Carthaginians, Dionysios learned the art of siege in this hard school. Ephoros numbered the Carthaginian invading force at 204`000, Timaios at 100`000. But even the smaller figure is probably too large; 40-50`000 is a more realistic estimate. A fleet containing 60 warships and 1`500 transports supported the army. That was a much more powerful force than the Athenians had mustered for their invasion of Sicily. Although the Athenians sent a larger battlefleet at 134 triremes, their army of 6`400 men was much smaller. Perhaps the most significant difference was the greater logistical support the Carthaginians enjoyed. Greeks in Sicily were prepared for passive siege warfare. Due to this threat, Dionysios set up a massive Research & Development program. He hired the best and brightest from around the world. Their assignment was to figure out new ways to perform siege warfare. Some anonymous inventors came up with the "Gastraphete" - a bellybow. The bellybow was also nicknamed "Katapeltikon". (Derived from 'Kata' a preposition meaning ‘Through’ - 'Pelta' a word referring to shields. Hence, Katapeltai means “through-shields”.) Dionysios surely saw the potential in this, and blessed their continued efforts to perfect this machine. A slightly larger version was created as well. These machines had no torsion power, only flexion - the bending of wood. Dionysios took these machines to use, mustered a great army, set up the first successful and efficient Greek supply train and logistics. While Greek siege-warfare in the Peloponnesian War was a pitiful effort compared to the methods of Easterners, Dionysios would prove that Greeks could do it as well as anyone. He eventually fought the Carthaginians away from the neutral Greek cities, and after some hardship went for the jugular of Carthaginian power in Sicily: Motya. Motya was the primary supplybase of Carthaginian interests in Sicily. This city, in Western Sicily, was a veritable fortress - for it was surrounded by water - it was an island in the bay of Lilybaeum. The entire length of this island was covered by a city wall. The only way to get to Motya was through a very narrow manmade mole connecting the mainland in the north with the island. The Carthaginians had demolished the mole prior to the Greeks setting up their operation there. Dionysios began the siege by setting his workers to repair the mole connecting the mainland to the island. Dionysios himself led his infantry against neighbouring cities and left his brother Leptines, who commanded the fleet, in charge of the construction. The mole was 1500 Meters long and 10 meters wide. Waters around Motya was quite shallow, making it easier. The circumference of the wall around Motya was about a mile and a half - with 20 towers 125 meters apart. Dionysios' ships were in a precarious position, but he began moving the ships over a thin strip of land. A Carthaginian commander, Himilco, saw his opportunity to attack. He hastened his fleet to attack the Greek ships before they were moved over land. But Dionysios' ingenuity and new invention saved the situation. As the Carthaginian ships hastened to attack, the Greeks drove them away with a hail of missile fire from archers on their ships, and from Dionysios' land-based catapults, whose greater range and accuracy had a great psychological effect. It may be that Dionysios' craftsmen had equipped their bellybows with winches, which would have made them still more powerful. When his men had completed the mole, Dionysios advanced his siege machinery against the walls in the vicinity of the northern gate. The citizens of Motya, cramped for space on their island city, had built their houses to a great height, reaching well above the walls. Dionysios built six-story siege towers to reach beyond the top of the walls and equal the height of the houses. Such tall siege towers probably exceeded the height of Carthaginian towers. The Greeks rolled these towers forward on wheels. Presumably teams of oxen pulled the towers. Xenophon tells us that Cyrus developed a means of hitching eight yoke of oxen inside the first story of his movable towers, moving around in single-file rotating a pole - driving the tower forward. This must have been the universal method of moving siege towers. Katapeltai helped drive the Motyan defenders off the wall while battering rams attacked it. The abundance of arrowheads among the ruins of the northern walls of Motya bear witness today to the intensity of their fire. It is important to note that this machine was, for all intents and purposes, designed to provide "covering fire" for the main siege operations, such as battering rams and siege towers. Making sure that resistance on the walls would be a minimum when the men reached the wall. Motya did not fall immediately. They fell back to their houses, which were set up in a contiguous circular line inside the wall, and these were as tall as the outer wall. It was essentially a second wall. The Greeks had to move their siege towers through the breaches and into the city and landed troops on the rooftops. Motya was razed to the ground. Qarthadast relocated their main base in Sicily to Lilybaeum...
E. W. Marsden, the most reknowned expert on ancient siege artillery who lived in the early 20th century, believed that it was Phillipos, the father of Megas Alexandros, who took the Katapeltes one step further beyond the primitive flexion-based design, with the use of torsion energy. If we can believe Polyainus, Phillipos's troops had been badly mauled in a field battle agains the Phokeis by non-torsion stonethrowing Katapeltai. Marsden believes this so impressed Phillip that he ordered his engineers to give special attention to the improvement of catapults. Chief among these engineers was a Thessalian named Polyidos, who became famous for his ingenuity. He wrote a work called "On Machines", and first revealed his genius in the siege of Byzantion. However, Phillipos's torsion catapults did not throw stones. Rather they applied torsion power to powerful composite bows that shot arrows. These machines then led to a standardized system of sizes. For Arrow Projectors, they used a system of length: span (23cm) and cubit (44.4cm). For Stone Projectors, they used systems of weight: Mna and Talanton.