trenches, raising parapets, sinking wells and bringing water into the camp. He likewise had the care of furnishing the troops with wood and straw, as well as the rams, onagri, balistae and all the other engines of war under his direction. This post was always conferred on an officer of great skill, experience and long service, and who consequently was capable of instructing others in those branches of the profession in which he had distinguished himself. At various locations described by Vitruvius, battles and sieges occurred. He is the only source for the siege of Larignum in 56 BC. Of the battlegrounds of the Gallic War there are references to: the siege and massacre of the 40,000 residents at Avaricum in 52 BC; Vercingetorix commented that "the Romans did not conquer by valor nor in the field, but by a kind of art and skill in assault, with which they [Gauls] themselves were unacquainted." The broken siege at Gergovia in 52 BC. The circumvallation and Battle of Alesia in 52 BC; the women and children of the encircled city were evicted to conserve food, where they starved to death between the opposing walls of the defenders and besiegers. And the siege of Uxellodunum in 51 BC. These are all sieges of large Gallic oppida. Of the sites involved in Caesar's civil war, we find the Siege of Massilia in 49 BC, the Battle of Dyrrhachium of 48 BC (modern Albania), the Battle of Pharsalus in 48 BC (Hellas – Greece), the Battle of Zela of 47 BC (modern Turkey) and the Battle of Thapsus in 46 BC in Caesar's African campaign. A legion that fits the same sequence of locations is the Legio VI Ferrata, of which ballista would be an auxiliary unit. Mainly known for his writings, Vitruvius was himself an architect. In Roman times architecture was a broader subject than at present including the modern fields of architecture, construction management, construction engineering, chemical engineering, civil engineering, materials engineering, mechanical engineering, military engineering and urban planning; architectural engineers consider him the first of their discipline, a specialization previously known as technical architecture. Frontinus mentions him in connection with the standard sizes of pipes. He is often credited as father of architectural acoustics for describing the technique of echeas placement in theaters. The only building, however, that we know Vitruvius to have worked on is one he tells us about, a basilica completed in 19 BC. It was built at Fanum Fortunae, now the modern town of Fano. The Basilica di Fano (to give the building its Italian name) has disappeared so completely that its very site is a matter of conjecture, although various attempts have been made to visualise it. The early Christian practice of converting Roman basilicae (public buildings) into cathedrals implies the basilica may be incorporated into the cathedral in Fano. In later years the emperor Augustus, through his sister Octavia Minor, sponsored Vitruvius, entitling him with what may have been a pension to guarantee financial independence. Whether De architectura was written by one author or is a compilation completed by subsequent librarians and copyists, remains an open question. The date of his death is unknown, which suggests that he had enjoyed only little popularity during his lifetime. Gerolamo Cardano, in his 1552 book De subtilitate rerum, ranks Vitruvius as one of the 12 persons whom he supposes to have excelled all men in the force of genius and invention; and would not have scrupled to have given him the first place, if it could be imagined that he had delivered nothing but his own discoveries. De