important factor in our navy — the manufacture of their engines called forth the utmost skill in design, ingenuity of detail, and accuracy of workmanship that were in those days available — but their end was near, and they were soon to become as obsolete and forgotten as though they had never been. Their defects and disadvantages had all along been sufficiently obvious, but nothing better was to hand. Huge outside cumbrous wheels, liable to be utterly disabled by the explosion of a lucky shell, the position of the engines themselves with their most vital parts well above the water line, and the enormous weight of the machinery in proportion to tonnage and horse power, all these objectionable characteristics made it certain that when an alternative method of propulsion was proposed by which these evils would be abrogated, or even sensibly mitigated, it would be welcomed with enthusiasm and eagerly adopted. The enthusiasm and the eagerness were not quite as much to the front as might have been expected, but the conservatism of the navy even now, much more then, may almost be termed bigotry. The screw propeller, however, had in itself such intrinsic merits that, if it did not at first dazzle like a display of fireworks, it soon became as much a national necessity as the breadstuffs it is the instrument of bringing in such quantities to us who would perish without them.
As has so frequently been the case with other inventions, it is not by any means certain to whom the credit of first discovering the screw as a propeller for marine purposes ought to be ascribed, but the matter is not of
