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 that might escape the most complete system of blockade. At no time has it been possible to prevent such attacks by an enterprising enemy, and there is perhaps greater opportunity for them with steam than before. Under such conditions special vessels for coast service have some justification, and confidence is maintained wherever the rest of the fleet is employed. The weak point of the principle is that the best coast defence vessel is a first-class battle ship, especially for an island subject at most periods of the year to weather that is not favourable to any but the most seaworthy craft.

For these reasons the coast defence ironclad, which is largely represented in other navies, is only found to a very limited extent in our own. The first of its kind, built about 1870, was designed with the idea that a type could be produced which might be equally useful for attack within a moderate distance from our shores and for defence in home waters. This was the 'Glatton,' a single-turreted monitor of 5000 tons. Her sides, which are very low, are protected with 12 in. of iron, and a similar thickness was placed on the turret. This is 38 ft. in diameter, and contains two muzzle loading 25-ton guns. When completed in 1872 an experiment was made to test the behaviour of the turret when struck by heavy projectiles. The 'Hotspur,' another vessel with a 25-ton gun, was moored at a convenient distance from the 'Glatton,' and a 600-lb. projectile fired at the turret of the latter. It failed to penetrate within or injure the rotating arrangements, the turret being found afterwards to revolve freely, and the guns it