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 its advantages to the utmost. To this laudable ambition we owe the introduction of forced draught and triple expansion. The former device, which, for the benefit of lay readers, may be defined as the increase of air pressure in the stokeholds by artificial means, causing the fires to burn more fiercely and to consume more fuel in a given time on the same surface of grate, was, like other new things, only generally adopted in our service after considerable hesitation, and when it had been proved by the French to possess certain advantages too weighty to be overlooked. It may be well here to observe that this is probably the first and only instance of British marine engineers owing anything to any foreign source. Other nations have invariably been content to follow where we led from the very earliest days of steam navigation. In the future it is possible that the restless ingenuity of American mechanicians may produce ideas that we cannot afford to neglect, but at present it may safely be said that the history of English engineering includes all that the rest of the world has hitherto accomplished in that direction.

Forced draught was first employed in the British navy in the 'Lightning,' our earliest torpedo boat, constructed by Messrs Thorneycroft, of Chiswick, in 1877. The system was adopted, primarily if not solely, with the view of obtaining a much greater power with a given weight of boilers than could be obtained with natural draught. Economy of fuel was not the object sought; if it had been, it would not have been found. The 'Lightning,' a boat only 84 ft. long, of 10 ft. 10. in.