The carriages used by Greeks and Romans were of various kinds, but though they expended large sums on the more splendid, yet in point of comfort their productions never approached the vehicles of modern coach-builders. The want of springs was an inconvenience, which they attempted to remedy by a luxurious array of feather cushions and down pillows. The carriages were either four-wheeled or two-wheeled; the former being mostly used in journeys. A pair of mules or horses were driven, and sometimes four. There is but little peculiarity in the manufacture of these carriages, but the shapes were elegant, and the poles or other parts were often elaborately carved, while the body of the car was perhaps tastefully inlaid. Traveling carriages in the later times were usually furnished with curtains to exclude the sun and air. Covered litters borne by slaves were also in common use among the wealthy for traveling short distances. The early history of the inventions by which men came to plough the watery deep, and to convert the element of seeming separation into one vast pathway for the mutual intercourse of nations, belongs to another province. Our space will only permit a brief account of the vessels used by the Greeks and Romans in the times of their more perfect nautical skill. The main division of these was into ships of war and ships of commerce. The former were long and narrow, propelled by rowers, and furnished generally with three ranks of oars, rising obliquely one above the other. But the numbers of these ranks varied much, and in one leviathan galley, built by Ptolemus Philopator, there were even forty ranks of rowers. The average number of the crew engaged in a ship of war was two hundred; and these vessels usually performed their voyages in short times, as the propelling power was independent of the wind. They were furnished with a pointed beak, singly or doubly cleft, and usually situated below the water-level, in order more effectually to run down the adversary. Ships of burden, on the contrary, were chiefly propelled by sails: their form was clumsy and heavy; of course they did not need the beak, and the number of their crews--the rowers especially--was small in comparison with the complements of men-of-war. With regard to the methods of propulsion, we may mention that sails and rigging were both very simple, as compared with the contrivances of our own days. There was usually only one sail--a large square-sail attached to the mainmast. But sometimes four were present, though even then all were not commonly employed together. The oars were of different lengths, in order to provide for the different heights of the rowers above the water-level. The ancient vessel was usually steered by two rudders or stern-oars, one being placed on either side of the stern. Swift, light galleys, with a large complement of rowers, were in use for performing expeditious voyages.