The Prefect of the camp, though inferior in rank to the [Prefect], had a post of no small importance. The position of the camp, the direction of the entrenchments, the inspection of the tents or huts of the soldiers and the baggage were comprehended in his province. His authority extended over the sick, and the physicians who had the care of them; and he regulated the expenses relative thereto. He had the charge of providing carriages, bathhouses and the proper tools for sawing and cutting wood, digging 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.
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.
Vitruvius is famous for asserting in his book De architectura that a structure must exhibit the three qualities of firmitas, utilitas, venustas – that is, it must be solid, useful, beautiful. These are sometimes termed the Vitruvian virtues or the Vitruvian Triad. According to Vitruvius, architecture is an imitation of nature. As birds and bees built their nests, so humans constructed housing from natural materials, that gave them shelter against the elements. When perfecting this art of building, the Greeks invented the architectural orders: Doric, Ionic and Corinthian. It gave them a sense of proportion, culminating in understanding the proportions of the greatest work of art: the human body. This led Vitruvius in defining his Vitruvian Man, as drawn later by Leonardo da Vinci: the human body inscribed in the circle and the square (the fundamental geometric patterns of the cosmic order).
In addition to providing his qualification, Vitruvius summarizes a recurring theme throughout the 10 books, a non-trivial and core contribution of his treatise outside simply a construction book. Vitruvius makes the point that the work of some of the most talented are unknown, while many who are of lesser talent but greater political position are famous. This theme runs through Vitruvius’s ten books repeatedly – echoing an implicit prediction that his works and himself will also be unknown.