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 when cruising would be about the same, and therefore her powers of ranging over the ocean would not exceed those of the 'Volage;' and, if the speed of the 'Volage' is adequate for the purpose, it is obvious that the protection of our commerce would be twice as effective, if we had double the number of ships.

Assuming, however, that extreme speed is required, it by no means follows that large tonnage is a necessity, The fastest vessel in the navy, the yacht 'Osborne,' is a comparatively small ship. The fastest ships in the merchant service are the steamers carrying the mails between Holyhead and Kingstown, and the blockade-runners which, during the war of the secession, escaped the United States cruisers by their superior speed. All these are ships of moderate size, when compared with the 'Inconstant.' True it is that her measured mile speed is such that she could escape from any ironclad that has been built; but unfortunately, at her extreme rate, she can only carry a supply of coal for 2¼ days' steaming. At the comparatively slow speed of 10 knots an hour, the 'Inconstant' can only carry coal for a distance of 2,160 miles, and could not therefore cross the Atlantic even at the moderate rate of 10 knots from Liverpool to New York.

Whatever be the rate attained on the measured mile, in cruising in search of an enemy, the speed of unarmoured vessels will seldom be allowed to exceed 10 knots. The great consumption of coal at higher speeds will make it impossible to exert the full power of the engines, except when giving chase to an enemy.