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values—guns trained on the broadside would point at intervals of four seconds from 10 degrees above the horizon to 10 degrees below it Ordinary vessels roll through larger angles, albeit in a greater time, but they undergo periods of comparative quiet when a gun can be laid with some degree of accuracy.

The monitor's artillery suffers the additional disadvantage of being so close to the water that it is only well up a fair-sized wave that another vessel can be seen, while the swash of water over the decks seriously interferes with the working of common turrets, although it will be observed that from so closely following the water surface much better weather is made than would at first be expected from the extreme lowness of free-board. For the same reason, the effective force on a person aboard being at each instant normal to the wave slope, the motion is much less apparent than in ordinary vessels, and a common short pendulum tending to set itself at right angles to the wave slope gives no indication of the motion of the ship with respect to the true vertical, so that the true roll of these vessels has been overlooked.

The surprise consequent on the comparatively good weather made by monitors in riding out heavy gales and afterwards in long voyages, and the very good work done by them in the attack of fortifications under conditions approaching those of their maximum efficiency, caused a reaction in naval opinion, originally unfavorable, until extravagant opinions were even expressed of their efficiency as cruisers for work on the high seas.

Under certain conditions of the attack and defense of harbors, the Board recognizes real advantages in the type. But it has no efficiency in protecting the coast and commerce from without the harbors, which, in the opinion of the Board, is the chief naval problem. Being further incapable of rapid mobilization and concentration under all conditions of weather, coast-defense by ships of this type would really amount to local defense of the principal harbors, when the enemy had been allowed, by the absence or defeat of our fleets on the high seas, to invest them.

That the same measure of defense can be obtained by very numerous and powerful sea-going fleets off the coast supplemented by monitor and shore defenses of the principal harbors, as with the vessels proposed by the Board, is unquestionable, but we are of opinion that greater security, with far greater economy, can be obtained by the type of battle-ships of limited endurance, capable not only of affording local defense to the harbors, but of rapid mobilization and concentration under all circumstances, and of acting with perfect confidence on the high seas.

In the opinion of the Board, the six vessels of the monitor type already provided for afford a sufficient proportion of purely harbordefense vessels.



United States Naval Institute.

Vol. XVI., No. 3. 1890. Whole No. 54.



By Ensign Albert A. Ackerman, U. S. N.

Part I.

The writer has freely employed information with regard to coast life-boats, derived from the publications of the U.S. Life-Saving Service; the Royal Life-Boat Institution of Great Britain; "Life-Boats, Projectiles, and other means for Saving Life," by the late R. B. Forbes; "The Life Boat," by Captain J. R. Ward, Chief Inspector of Royal Life-Boat Institution; "History of the Life-Boat and its Work," by Richard Lewis; and " Specifications for U. S. Life-Saving Stations and Surf Boats."

With regard to the use of life-boats aboard ship little has been written, and that by either landsmen or those unacquainted with the peculiar needs of a man-of-war. Still, the writer can claim to have developed but litde that is new. It has been his effort to state the case plainly and justly, to form an unprejudiced opinion, and to bring out points of practical and direct application aboard ship. The temptation to touch on the general features of policy and organization has been irresistible; but once committed, their criticism has been actuated

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