On Architecture
Vitruvius Pollio
Vitruvius Pollio, creator; Morgan, M. H. (Morris Hicky), 1859-1910, translator
1. THERE is also another kind of tortoise, which has all the other details as described above except the rafters, but it has round it of boards, and eaves sloping down
2. It does not seem to me out of place to set forth the principles on which Hegetor of Byzantium constructed a tortoise. The length of its base was sixty-three feet, the breadth forty-two. The corner posts, four in number, which were set upon this framework, were made of two timbers each, and were thirty-six feet high, a foot and a quarter thick, and a foot and a half broad. The base had eight wheels by means of which it was moved about. The height of these wheels was six and three quarters feet, their thickness three feet. Thus constructed of three pieces of wood, united by alternate opposite dovetails and bound together by cold-drawn iron plates, they revolved in the trees or amaxopodes.
3. Likewise, on the plane of the crossbeams above the base, were erected posts eighteen feet high, three quarters of a foot broad, two thirds of a foot thick, and a foot and three quarters apart; above these, framed beams, a foot broad and three quarters of a foot thick, held the whole structure together; above this the rafters were raised, with an elevation of twelve feet; a beam set above the rafters united their joinings. They also had bridgings fastened transversely, and a flooring laid on them protected the parts beneath.