Legion Artifices Fabricate Siege Apparatus

Read beyond Vegetius’ tables and you find hands. He writes that within a legion, artifices—skilled artisans—construct “testudines,” protective sheds; “arietes,” rams; and “turres ambulatoriae,” mobile towers. The list broadens artillery into an ecosystem of wood, hide, and iron that moves with the army [4].

This is the line that connects Camillus’ tunnelers at Veii to late-imperial camps. Early Rome improvised underground when engines failed [6]; by Vegetius’ day, Rome trained for the routine above ground: build cover, build blow, build height. The noise in camp near Aquileia is industrious—hammers striking rivets; saws rasping; the creak of rawhide skeins as a scorpion takes its first turns.

Artifices turn doctrine into mass. A testudo—shed—needs a measured width to cover a ram’s swing; a tower needs a base that won’t sink into a trench; a ram needs a nose shaped to bite mortar. Vitruvius’ insistence on proportion sits in the background even when the machine is not torsion-bound [1]. Frontinus’ stratagems live here too: a shed makes a ruse safe; a tower makes a feint plausible [7].

The army’s geography demands this portability. In Gaul, an oppidum; on the Danube, a riverside fort; in Africa, a walled town. A legion learns to make its own tools from local timber and iron brought on carts. That is why Vegetius can imagine 55 carroballistae and 10 onagers as part of a moving establishment—the artifices can keep them alive, repair a cracked peritrete, fashion a new ram head, patch a tower’s hide with fresh rawhide [4].

Visuals help. On Trajan’s Column, the tower frames are there in stock; the carts hauling ballistae imply workbenches somewhere behind the scenes [9][11]. In Jerusalem, the vineae—the covered sheds—rock forward as stones thump into parapets [2]. Ammianus later tells us how a ram breaks a wall—“buildings are cracked and shattered as the structure of their walls is destroyed”—and the artifices’ work is the blow that makes that sentence true [3].

In a late camp, the colors are earthy: pale hide, dark timber, iron dulled with grease. The tools lay in rows; apprentices learn the ninths of a spring-hole and the proper curve of a ram’s nose. When an alarm sounds, half the workshop turns soldier; the other half keeps building. That duality—craftsman and fighter—is how the legion keeps its siege kit more than alive. It keeps it ready.