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HISTORY OF MARINE ARCHITECTURE.

thought to militate against general opinion, it must be observed, that theredoes not perhaps exist any certain refutation of it: nor, indeed, should any,short of some well preserved remnant of antiquity, sufficiently authenticated byeither its inscription, or its general appearance, as being the representation of someparticular object of our controversy, be very readily admitted. It is an oldand trite maxim, but not the less true, on that account, that men with difficultycomprehend mere description ; and are scarcely satisfied as to the existence ofany thing that they do not actually behold.

The principal dimensions of different classes of vessels in use among the an-cients, as well as of those which were of such extraordinary magnitude as to beextremely uncommon, and rarely constructed, have been transmitted to posteritywith much apparent certainty and precision. The celebrated ^Egyptian vessel,called the Isis, is said to have been in length one hundred and eighty feet, in breadthforty-five, and in height, from the upper edge of the deck to the bottom of thewell, forty-three feet. The well-known ship of Hiero, king of Syracuse, wasof nearly four thousand tons burthen. The rules of construction in general use,for those which were usually employed in commerce, after the art had progres-sively advanced toward, what was then supposed perfection, were in the followingproportion: supposing the breadth twenty-five feet, the length was one hundred.The gallies which were intended intirely for the purposes of war, were twicethat length, but of the same breadth ; nor can that very extensive difference bedeemed incredible, or even wonderful, when it is known, that, even in moderntimes, vessels, 110 less extravagantly proportioned, have been built for particularpurposes, and have proved by no means ill adapted to them.

Meibomius gives the following dimensions of the ancient Roman Triremes :“ They were,” says he, “ in length one hundred and five feet; in breadth eleven ;but, according to new regulations, adopted after the time of Julius Cesar, theywere built only ninety feet in length, and ten in breadth : the Quadriremewas one hundred and twenty-five feet long, and thirteen broad : the heightof the Octoreme, (as the same author asserts) measured, from the upper surfaceof the deck to the lower edge of the keel, eleven feet:' the Hexereme nine.”Their first requisite, as there has already been occasion to remark, was swiftness :on that principally depended the success of all their naval encounters *; and every

* There cannot therefore be much wonder at the same principles being adhered to, on some occa-sions, in later times.

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