In 1868 the Dutch Government received from English builders two single turret ironclad monitors, intended for harbour defence, which were stated to be the first of the low freeboard type completed in this country, and carrying turrets on Captain Coles’s system. These vessels, the _Krokodil_ and _Heiligerlee_, were about 180 feet in length, with a beam of 44 feet, and a depth of 11 feet 6 inches. From the gunwale to 8 feet below the water-line they had iron armour-plates of a total thickness of 5½ inches, tapering off to 4½ inches at the extreme ends. This armour rested against a teak backing 10 inches in thickness, behind which was an inner skin of 1-inch iron, and inside this again was a series of longitudinal iron girders. For their size they were exceedingly strongly constructed, but as they were designed to be able to meet any hostile vessel which might approach any of the harbours of the shallow Dutch coast where they might be stationed, the reason for such substantial construction is apparent. The turret armour was 11 inches thick at the gunports, and 8 inches thick elsewhere. The armament consisted of two 12½-ton rifled guns firing a 300 lb. projectile, which could be discharged from within four degrees of aft on either side to direct ahead. The turrets could be revolved by steam or hand power as desired. The twin-screw engines were of 140 h.p. nominal. Another vessel of considerable interest, designed and built for the Dutch Government by Napier, was the turret gunboat _De Tygre_, which inaugurated a type which found much favour in Holland. This vessel, of 187 feet in length, 44 feet breadth, and moulded depth 11 feet 6 inches, and of 1,613 tons, builder’s measurement, was built in compartments and with watertight doors, and was like most of the turret ships of the monitor variety, as she had a double bottom which could be filled with water to sink her to her fighting level. Thus only about 2 feet of her topsides would be exposed to the enemy. As an improvement upon her came another vessel from the same builders, which was described as “of a build which has long seemed to us as one of those most likely to become employed for the ‘ship of the future,’ not because she is a ram, but because she is essentially a sea-going turret ship.” She was “the _De Tygre_ over again, with the following exceptions: She has about 3 feet less beam, a rather greater draught of water, and light topsides are raised over the armour-plating and the deck, with which it terminates to the level of another deck; the vessel is thus in appearance an ordinary sea-going ship of war, for she is pierced for a few light guns on the lower deck; but her fighting strength consists in her turret, which is similar to that of the _De Tygre_, except that the ports are at a higher elevation. This vessel is, therefore, a cruiser, unarmoured, higher than a level of 2 feet from the water; but practically for a fight at close quarters she is a