The Romans were not at first so strong in naval power as their neighbours, but in order to keep pace with them they were ultimately compelled to devote more attention to their navies. About 260 B.C. they raised a large fleet to carry on the war with Carthage. A Carthaginian quinquereme which happened to be wrecked on their coast was taken possession of by the Romans, used as a model, and one hundred and thirty ships constructed from it. These ships were all built, it is said, in six days; but this appears almost incredible. We must not, however, judge the power of the ancients by the standard of present times. It is well known that labour was cheap then, and we have recorded in history the completion of great works in marvellously short time, by the mere force of myriads of workmen. The Romans not only succeeded in raising a considerable navy, but they proved themselves ingenious in the contrivance of novelties in their war-galleys. They erected towers on the decks, from the top of which their warriors fought as from the walls of a fortress. They also placed small cages or baskets on the top of their masts, in which a few men were placed to throw javelins down on the decks of the enemy; a practice which is still carried out in principle at the present day, men being placed in the "tops" of the masts of our men-of-war, whence they fire down on the enemy. It was a bullet from the "top" of one of the masts of the enemy that laid low our greatest naval hero, Lord Nelson. From this time the Romans maintained a powerful navy. They crippled the maritime power of their African foes, and built a number of ships with six and even ten ranks of oars. The Romans became exceedingly fond of representations of sea-fights, and Julius Caesar dug a lake in the Campus Martius specially for these exhibitions. They were not by any means sham fights. The unfortunates who manned the ships on these occasions were captives or criminals, who fought as the gladiators did-- to the death--until one side was exterminated or spared by imperial clemency. In one of these battles no fewer than a hundred ships and nineteen thousand combatants were engaged! Such were the people who invaded Britain in the year 55 B.C. under Julius Caesar, and such the vessels from which they landed upon our shores to give battle to the then savage natives of our country. It is a curious fact that the crusades of the twelfth and thirteenth centuries were the chief cause of the advancement of navigation after the opening of the Christian era. During the first five hundred years after the birth of our Lord, nothing worthy of notice in the way of maritime enterprise or discovery occurred.