Our knowledge of Greek fighting ships—thanks to Greek literature—is fairly full. In the time of Homer, about ten centuries before Christ, Greek men-of-war carried crews of from fifty to one hundred and twenty men, nearly all of whom took part in the labor of rowing. A military boat called the "bireme" came into use in Greece about six or seven centuries before Christ. The word means a vessel with two rows or banks of oarsmen on each side, one row above the other. This disposition of rowers was evidently for the purpose of securing the largest possible number in the least possible space. It is probable that the Greeks did not originate the bireme, but borrowed the idea from the Phœnicians or possibly from Egypt. When Athens was at the zenith of her glory, the principal war vessel was the "trireme," a ship with three rows of oarsmen to the side, each rising above another. Larger ships were subsequently constructed with four, five, and even sixteen banks of rowers to a side, tier above tier.
The Romans, although they were so powerful in land warfare, were not strong in naval achievement until after the First Punic War. In this war they learned the art of naval construction from their enemies, the Carthaginians. A Carthaginian "quinquereme," or boat with five banks of oars, drifted to the Roman coast. The Romans copied it, set up frames on dry land in which crews were taught to row, and in sixty days from the time the trees were felled they had built and manned a fleet. Later the Romans used grappling hooks with which they bound together their own and an opposing ship. They then boarded the enemy's vessel and carried on the fight at close quarters. These tactics gave the Romans command of the sea, and their war galley came to be the supreme object of terror in the naval history of Roman days.
Sails and wind superseded rowers as the motive force of ships. Then came steam. But after gunpowder and steam had worked a revolution in the modes of naval combat, vessels of war continued to be made of wood.
The first fight between iron ships in the history of the world was fought on the ninth of March, 1862, in Hampton Roads, near Norfolk, Virginia, during the Civil War in America. The battle was the combat between the Merrimac and the Monitor. This engagement marked the end of wooden navies. Thenceforth the nations of earth were to make their warships of iron and steel.
Among the largest battleships built for the United States navy are the Delaware and the North Dakota. Each of these battleships is five hundred and ten feet long, a little more than eighty-five feet wide, sinks to the depth of nearly twenty-seven feet in the water, and travels at the rate of twenty-one knots per hour. Each vessel weighs twenty thousand tons, and is armed with ten great guns a foot in diameter at the mouth. The North Dakota required 4688 tons of steel armor at a cost of more than four hundred dollars per ton. Each of its great twelve-inch guns cost nearly $110,000, weighs fifty-two tons, and hurls a projectile weighing 850 pounds a distance of twelve miles. Three hundred and eighty-five pounds of powder are consumed at a single discharge. At a distance of more than a mile and a half the projectiles of the North Dakota will penetrate steel armor to a depth of nearly twenty inches. When these projectiles leave the guns, they fly through the air at the rate of 2,800 feet in a second. When one hundred shots have been fired from one of these guns, it is worn so that it will be useless until repaired. The cost of a single discharge from one of these guns is about $350.
Sub-marine navigation has always been attended by the most woeful catastrophes, but in spite of numerous accidents the development of the submarine boat has progressed uninterruptedly. Each new model presents new preventive devices. Flasks of oxylithic powder are carried for purifying the air in the water-tight compartments in which the crews live while the boat is below the surface of the water. There is also a special apparatus for signalling other vessels or the shore, in case of danger. In 1904 three vessels, designated X, Y, and Z, were completed, which could achieve submersion in the short space of two minutes. The boats were armed with six torpedoes each. France owns the largest fleet of under-water warships in the world. England stands next, and the United States government is third.
CHAPTER VIII
ASTRONOMICAL DISCOVERIES AND INVENTIONS
"When I consider thy heavens, the work of thy fingers, the moon and the stars, which thou hast ordained, what is man, that thou art mindful of him?" The Hebrew psalmist feels the insignificance of man compared with the infinitude of the heavens. Victor Hugo expresses the opposite thought: "There is one spectacle grander than the sea—that is the sky; there is one spectacle grander than the sky—that is the interior of the soul."