|Youre here: Home » eDigg Biographies » Biographies A-F » Archimedes|
It is scarcely possible to view the vast steamships of our day without reflecting that to a great master of mechanics, upward of two thousand years since, we in part owe the invention of the machine by which these mighty vessels are propelled upon the wide world of waters. This power is an application of "the Screw of Archimedes," the most celebrated of the Greek geometricians. He was born in Sicily, in the Corinthian colony of Syracuse, in the year 287 B.C., and when a very young man, was fortunate enough to enjoy the patronage of his relative Hiero, the reigning prince of Syracuse.
Death of Archimedes.
Travelling in Egypt, and observing the necessity of raising the water of the Nile to points which the river did not reach, as well as the difficulty of clearing the land from the periodical overflowings of the Nile, Archimedes invented for this purpose the screw which bears his name. It was likewise used as a pump to clear water from the holds of vessels; and the name of Archimedes was held in great veneration by seamen on this account. The screw may be briefly described as a long spiral with its lower extremity immersed in the water, which, rising along the channels by the revolution of the machine on its axis, is discharged at the upper extremity. When applied to the propulsion of steam-vessels the screw is horizontal; and being put in motion by a steam-engine, drives the water backward, when its reaction, or return, propels the vessel.
The mechanical ingenuity of Archimedes was next displayed in the various machines which he constructed for the defence of Syracuse during a three years' siege by the Romans. Among these inventions were catapults for throwing arrows, and ballistae for throwing masses of stone; and iron hands or hooks attached to chains, thrown to catch the prows of the enemy's vessels, and then overturn them. He is likewise stated to have set their vessels on fire by burning-glasses; this, however, rests upon modern authority, and Archimedes is rather believed to have set the ships on fire by machines for throwing lighted materials.
After the storming of Syracuse, Archimedes was killed by a Roman soldier, who did not know who he was. The soldier inquired, but the philosopher, being intent upon a problem, begged that his diagram might not be disturbed; upon which the soldier put him to death. At his own request, expressed during his life, a sphere inscribed in a cylinder was sculptured on his tomb, in memory of his discovery that the solid contents of a sphere is exactly two-thirds of that of the circumscribing cylinder; and by this means the memorial was afterward identified. One hundred and fifty years after the death of Archimedes, when Cicero was residing in Sicily, he paid homage to his forgotten tomb. "During my quaestorship," says this illustrious Roman, "I diligently sought to discover the sepulchre of Archimedes, which the Syracusans had totally neglected, and suffered to be grown over with thorns and briars. Recollecting some verses, said to be inscribed on the tomb, which mentioned that on the top was placed a sphere with a cylinder, I looked round me upon every object at the Agragentine Gate, the common receptacle of the dead. At last I observed a little column which just rose above the thorns, upon which was placed the figure of a sphere and cylinder. This, said I to the Syracusan nobles who were with me, this must, I think, be what I am seeking. Several persons were immediately employed to clear away the weeds and lay open the spot. As soon as a passage was opened, we drew near, and found on the opposite base the inscription, with nearly half the latter part of the verses worn away. Thus would this most famous, and formerly most learned, city of Greece have remained a stranger to the tomb of one of its most ingenious citizens, had it not been discovered by a man of Arpinum."
To Archimedes is attributed the apophthegm: "Give me a lever long enough, and a prop strong enough, and with my own weight I will move the world." This arose from his knowledge of the possible effects of machinery; but however it might astonish a Greek of his day, it would now be admitted to be as theoretically possible as it is practically impossible. Archimedes would have required to move with the velocity of a cannon-ball for millions of ages to alter the position of the earth by the smallest part of an inch. In mathematical truth, however, the feat is performed by every man who leaps from the ground; for he kicks the world away when he rises, and attracts it again when he falls back.
Under the superintendence of Archimedes was also built the renowned galley for Hiero. It was constructed to half its height, by three hundred master workmen and their servants, in six months. Hiero then directed that the vessel should be perfected afloat; but how to get the vast pile into the water the builders knew not, till Archimedes invented his engine called the helix, by which, with the assistance of very few hands he drew the ship into the sea, where it was completed in six months. The ship consumed wood enough to build sixty large galleys; it had twenty tiers of bars and three decks; the middle deck had on each side fifteen dining apartments besides other chambers, luxuriously furnished, and floors paved with mosaics of the story of the "Iliad." On the upper deck were gardens with arbors of ivy and vines; and here was a temple of Venus, paved with agates, and roofed with Cyprus-wood; it was richly adorned with pictures and statues, and furnished with couches and drinking-vessels. Adjoining was an apartment of box-wood, with a clock in the ceiling, in imitation of the great dial of Syracuse; and here was a huge bath set with gems called Tauromenites. There were also on each side of this deck, cabins for the marine soldiers, and twenty stables for horses; in the forecastle was a fresh-water cistern which held 253 hogsheads; and near it was a large tank of sea-water, in which fish were kept. From the ship's sides projected ovens, kitchens, mills, and other offices, built upon beams, each supported by a carved image nine feet high. Around the deck were eight wooden towers, from each of which was raised a breastwork full of loopholes, whence an enemy might be annoyed with stones each tower being guarded by four armed soldiers and two archers. On this upper deck was also placed the machine invented by Archimedes to fling stones of 300 pounds weight and darts eighteen feet long, to the distance of 120 paces; while each of the three masts had two engines for throwing stones.
The ship was furnished with four anchors of wood and eight of iron; and "the water-screw" of Archimedes, already mentioned, was used instead of a pump for the vast ship; "by the help of which one man might easily and speedily drain out the water, though it were very deep." The whole ship's company consisted of an immense multitude, there being in the forecastle alone 600 seamen. There were placed on board her 60,000 bushels of corn, 10,000 barrels of salt fish, and 20,000 barrels of flesh, besides the provisions for her company. She was first called the Syracuse, but afterward the Alexandria. The builder was Archias, the Corinthian shipwright. The vessel appears to have been armed for war and sumptuously fitted for a pleasure-yacht, yet was ultimately used to carry corn. The timber for the main mast, after being in vain sought for in Italy, was brought from England. The dimensions are not recorded, but they must have exceeded those of any ship of the present day; indeed, Hiero, finding that none of the surrounding harbors sufficed to receive his vast ship, loaded it with corn and presented the vessel with its cargo to Ptolemy, King of Egypt, and on arriving at Alexandria it was hauled ashore, and nothing more is recorded respecting it. A most elaborate description of this vast ship has been preserved to us by Athenaeus, and translated into English by Burchett, in his "Naval Transactions."
Archimedes has been styled the Homer of geometry; yet it must not be concealed that he fell into the prevailing error of the ancient philosophers--that geometry was degraded by being employed to produce anything useful. "It was with difficulty," says Lord Macaulay, "that he was induced to stoop from speculation to practice. He was half ashamed of those inventions which were the wonder of hostile nations, and always spoke of them slightingly, as mere amusements, as trifles in which a mathematician might be suffered to relax his mind after intense application to the higher parts of his science."
|Copyright © 1999-2008 eDigg.com. All rights reserved.|