Nevertheless, as it is quite clear that Ptolemy did construct a galley of unusual size and capacity, modern commentators have earnestly sought to explain away the glaring exaggerations and impossibilities of the description given by Callixenus. The chief difficulty lay in the forty tiers of oars and in the four thousand oarsmen. The engraving upon the opposite page gives a representation of the Ptolemy, as she may reasonably be supposed to have appeared. Instead of forty _tiers_, she has, when thus restored, forty _groups_ of oars: with this substitution, and a liberal diminution in the aggregate number, it is not improbable that she may have existed, and floated even. It is not, however, pretended by Callixenus that she was ever useful in war: she seems to have been regarded as a curiosity and a spectacle. She was, in fact, the Leviathan of antiquity,--the original "Triton among the minnows." [Illustration: THE PTOLEMY PHILOPATOR.] The Romans obtained the models of their vessels from the Greeks, though they remained almost entirely unacquainted with the sea till the third century before Christ. They then had no fleet, and few or no ships for any peaceful or commercial use. Livy mentions the appointment of naval decemvirs about the year 300 B.C. But it was not till 260 B.C. that Rome became a maritime power. It was now seen that she could not maintain herself against Carthage without a navy, and the senate ordered the immediate construction of a fleet. Triremes would have been of little avail against the high-bulwarked quinqueremes of the Carthaginians. It so happened, very fortunately for them, that a vessel of the largest class, belonging to Carthage, was wrecked upon the coast of Bruttium, and thus furnished them a model. They built, after this design, over one hundred vessels, the greater part of them quinqueremes, the whole being completed in sixty days after the trees were cut down. Thus built of green timber, they were unsound and clumsy. Still, to their own astonishment, they achieved a naval victory, capturing fifty of the enemy's vessels. Seventeen of their own were taken and destroyed by the Carthaginians off Messina. It was not long before the Romans completely crippled the maritime power of their African foe. From this time forward they continued to maintain a powerful navy, and built vessels with six and even ten ranks of oars. The construction of their vessels differed little from that of the Greeks, with the exception of the destructive engines of war and the towers and platforms with which they furnished them.