In the most ancient accounts of the Grecian ships, the only mode by which we can form a conjecture of their size, is from the number of men they were capable of holding.  At the siege of Troy, Homer describes the ships of the Beotians as the largest; and they carried, he says, one hundred and twenty men.  As Thucydides informs us that at this period soldiers served as rowers, the number mentioned by Homer must comprehend all the ship could conveniently accommodate.  In general the Roman trading vessels were very small.  Cicero represents those that could hold two thousand amphorae, or about sixty tons, as very large; there were, however, occasionally enormous ships built:  one of the most remarkable for size was that of Ptolemy; it was four hundred and twenty feet long, and if it were broad and deep in proportion, its burden must have been upwards of seven thousand tons, more than three times the burden of one of our first rates; but it is probable that it was both flat bottomed and narrow.  Of the general smallness of the Greek and Roman ships, we need no other proof, than that they were accustomed to draw them on land when in port, and during the winter; and that they were often conveyed for a considerable space over land.  They were sometimes made in such a manner that they could easily and quickly be taken to pieces, and put together again.  Thucydides asserts that the ships which carried the Greeks to Troy were not covered; but in this he is contradicted by Homer.

The principal officer in ships intended for trade was the pilot:  he was expected to know the right management of the sails, rudder, &c. the wind, and celestial bodies, the harbours, rocks, quick-sands, and course to be steered.  The Greeks were far behind the Phoenicians in many parts of nautical knowledge:  we have seen that the latter at an early period changed the Greater for the Lesser Bear, for the direction of their course; whereas the Greeks steered by the Greater Bear.  In very early periods it was the practice to steer all day by the course of the sun, and at night to anchor near the shore.  Several stars were observed by the pilot for the purpose of foretelling the weather, the principal of which were Arcturus, the Dog Star, Orion, Castor and Pollux, &c.  In the time of Homer, the Greeks knew only the four cardinal winds; they were a long time ignorant of the art of subdividing the intermediate parts of the horizon, and of determining a number of rhombs sufficient to serve the purposes of a navigation of small extent.  Even so late as the date of the Periphes of the Erythraean Sea, which Dr. Vincent has fixed about the tenth year of Nero’s reign, only eight points of the compass are mentioned; these are the same as are marked upon the temple of the winds at Athens.  The utmost length to which the ancients arrived in subdividing the compass, was by adding two intermediate winds between each of the cardinal winds.  We have noticed these particulars relative to the winds and the constellations, in order to illustrate the duty which the pilot had to perform, and the difficulty and responsibility of his office, at a period when navigators possessed such a small portion of experience and knowledge.