One of these extraordinary vessels is described at length in Athenæus,[174] from an Alexandrian historian named Callixenus. The following are some of her chief peculiarities: she is said to have been two hundred and eighty cubits long, thirty-eight broad, and fifty-three from the highest part of the stern to the water; she had four rudders, each thirty cubits long; and the oars of the _thranitæ_ were thirty-eight cubits long, with handles necessarily weighted with lead. She had two heads, two sterns, and no fewer than seven beaks, one of them much larger than the rest. She carried on board four thousand rowers, and about three thousand mariners, besides a large body of men under her decks, and a vast quantity of stores and provisions. She was launched by means of a contrivance invented by a Phœnician, one, indeed, which might probably have been adopted with success for the launching of the Great Eastern, and, assuredly, at less cost. [Sidenote: Analysis of her dimensions.] [Illustration: GREAT SHIP OF PTOLEMY PHILOPATOR.] Various imaginary drawings have been made of Ptolemy’s great vessel; but as none of them appear to answer the only description of her which has been preserved, or to fulfil the requirements of a structure meant to float in safety, an endeavour has been made, in the drawing annexed, to illustrate this remarkable ship, which was “well proportioned in an extraordinary degree.”[175] If the cubit be taken at eighteen inches, Ptolemy’s ship was four hundred and twenty feet in length, fifty-seven feet beam, and had seventy-two feet depth of hold: proportions which, as far as regards the length and breadth, accord very well with those of the large steam-ships of our own time; but the depth is so great and so much out of proportion to the length and breadth, that there is no doubt a mistake in the figures. The depth was much more likely to have been twenty-eight cubits, for which forty-eight has, through some misapprehension, been substituted. There is no doubt, also, a mistake in the height of the stern above the water, for though the ships of the ancients had frequently very high poops or enormous castles erected aft, a practice which prevailed up to the seventeenth century, it is hardly possible to conceive that the highest portion of the poop of Ptolemy’s ship was fifty-three cubits, or about eighty feet above the water. The object of having so many as seven beaks is not easily understood; two of them may, however, have been placed at the bluff, or rounds of the bows, so as to protect, in some measure, the oars from being destroyed by the ship of an enemy sheering alongside. “Some of them,” we are informed, “were fixed to the ears of the ship.”