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HISTORY OF MARINE ARCHITECTURE.

veyed to the water side, where it was formed into a solid hull, the balks beinrclamped together with iron, and the whole hewn into that species of formwhich resembled the bottom of a ship. In the centre of the vessel, if it could besaid to deserve that name, was a hollow, which served not only for the lodgmentof the crew, but as a receptacle for the few stores and provisions which werenecessary to their maintenance. It was supposed, that the natural buoyancy ofthe float, or raft, for the latter seems to be the most appropriate term that can beapplied to it, would not only totally prevent those accidents which frequentlyattend'navigation, but that the natural security from danger was so strong asto remove every possible apprehension of danger, or risk. The event, how-ever, proved this opinion to have been too hastily formed; for of eight or tenvessels, or floats, so constructed, which sailed from America, not half ofthem ever reached the intended port of their destination. The remainderhaving never been heard of, were supposed to have foundered at sea; amisfortune which, in general opinion, was occasioned by the cramps of iron,which confined the balks in their intended place, having proved insufficient tothe performance of their office: when the joint agitation and force, as well ofthe wind as the sea, acted on the float, and necessarily caused that violentstrain, the effects were not to be parried, except by that species of mechanism,called, in ship-building, the frame of a vessel. The latter being cased with plank,so as to exclude the water, forms an irregular kind of elliptical arch, in which allthe parts mutually support and afford such protection to each other, as enablesthem to resist with success, those assault^ which, without such combination,would inevitably, and almost instantaneously, destroy the whole mass*.

By far- the greater part of the American marine was, as already observed.,intended solely for the purposes of commerce, and the deviation from the prac-tice of Britain in the same branch, at this period, was so extremely immaterialas to render any distinct description of it unnecessary. But there exists aclass of vessels peculiar, not indeed, to the continent itself, but to one of the

* Instances are not wanting which clearly, prove, that the preservation of vessels has frequentlybeen owing to the constant pressure of the fluid on the hull, by which action all the component partsof it have been confined in their proper and allotted place, which from the form, and circumstancesabove stated, were enabled to resist its further impulse. Ships, although known to be-in a conditionvery unfit for sea, have, nevertheless, frequently completed their voyage in safety, but when tpken intodock for thp purpose of repair, or examination, on becoming deprived of that, continual support whichthey derived from the water which surrounded them when in a floating state, have actually fallen topieces, owing to the deprivation just mentioned.

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