[85] Vitruvius, De Architectura, x. 13, § 3, mentions among Roman scaling-machines, an inclined plane, “ascendentem machinam qua ad murum plano pede transitus esse posset.”
[86] Guillaume le Breton, Philippis, book vii. This poem is an important source of information for the wars of Philip Augustus, and for the siege of Château-Gaillard in particular.
[87] Ord. Vit., ix. 13.
[88] Ibid., ix. 11.
[89] Ibid., xii. 36.
[90] This is the usual distinction. But the use of the names varies. In Vitruvius (op. cit., x. 10, 11) the catapulta or scorpio is a machine for shooting arrows, while the ballista is used for throwing stones. The pointed stakes at the siege of Marseilles (Cæsar, De Bell. Civ., ii. 2) were shot from ballistae. Vitruvius indicates several methods of working the ballista by torsion: “aliae enim vectibus et suculis (levers and winches), nonnullae polyspastis (pulleys), aliae ergatis (windlasses), quaedam etiam tympanorum (wheels) torquentur rationibus.”
[91] For the injuries inflicted by stone-throwing machines, see Villehardouin’s mention of the wounding of Guillaume de Champlitte at Constantinople, and of Pierre de Bracieux at Adrianople.
[92] Oman, op. cit., 139, quotes Anna Comnena to this effect.
[93] Stone-throwing engines and ballistae alike were employed by the Saracens at Mansurah (1250), for hurling Greek fire at the towers constructed by St Louis to protect his causeway-makers (Joinville).
[94] Thus, in the first siege of Constantinople by the Crusaders (1203), Villehardouin emphasises the number of siege-machines used by the besiegers upon shipboard and on land, but gives no account of their use by the defenders. They were employed, however, by the defence, as we have seen at Marseilles; see also Chapter [I]. above, for possible traces of their use in the stations of the Roman wall. A special platform might in some cases be constructed for them and wheeled to the back of the rampart-walk.