HISTORY OF MARINE ARCHITECTURE.

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for a Maltese or Neapolitan galley to row sixty leagues in the course of thetwenly-four hours. It is moreover positively affirmed, that a galley has madethe passage from Naples to Palermo in seventeen hours, and from Genoa toMarseilles in a day. That a fair comparison may be drawn, in this respect,between the ancient Triremes, or galleys of that class, and the Liburni, it willbe necessary to enquire what was the impelling power in both instances. It isan opinion deduced by Vossius from a very laboured and arithmetical statement,which it is not of any consequence to repeat here, that a modern galley movesforward nearly thirty feet at each stroke or pull of the oars. It is very evident,by a calculation drawn from the same principles, that the Trireme moved for-ward only twenty-five feet and a fraction.

Vessels of burthen differed, as has been before observed, very materially, bothin their equipment and outline, from those intended for w ar: the latter weredenominated Naves Longae, the former, owing to their peculiarity of construc-tion, Naves Rotundas. The difference in their sailing is computed to havebeen as two to three; and experiments which w r ere made even in those ageson the relative swiftness or speed of vessels, fully proved that a galley of war,using her oars only, surpassed in speed any merchant vessel that employed all hersails, and every other possible means of expediting her passage. If vessels of bothdescriptions used their sails, the pre-eminent advantage was still maintained inthe same degree, by the galley, which it had before possessed when workedwith oars. It is too apparent even to demand explanation, that where the headresistance of the fluid is once overcome, the collateral friction being very trifling,it follows, that the longer the vessel the greater quantity of impelling power canbe used. To this circumstance may also be added the very weighty consideration,that a galley of war being of much lighter draught of w'ater than a loaded vessel,had consequently so much the less opposing pow'er to overcome in that respect,and being much less liable to pitch in the swell of the sea than a short vessel,would consequently, in that respect also, have inferior difficulties to overcome.These several principles are so well established by modern practice and expe-rience, that it is needless to expend any farther time in stating or explainingthem.

A considerable number of additions and improvements made on the originalinvention having descended into modern use almost without alteration, therebecomes no necessity of doing more than simply enumerating them. In thisclass may be included the mr st and sail, invented by Daedalus, or, according to

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