On the 13th three new monitors had arrived from Rio Janeiro, and joined their squadron. They were built in Rio Janeiro, and had twin screws, with four inches of iron on the hull, which was only one foot out of the water, when prepared for action in fresh water. They had each one revolving turret, six inches thick, with one heavy Whitworth gun in each. The circular port for the gun was barely larger than the muzzle, and when run out was flush with the face of the turret. Elevation and depression of a gun so placed was obtained by means of a double carriage, which raised or lowered the trunnions. On February 18th everything was ready, and at half past three in the morning the Brazilians began to bombard the Paraguayan works most furiously. The large casemate ironclads, each with a monitor lashed alongside, then steamed up to the batteries at Humáitá. The fire of these batteries was well sustained, and true, as the Paraguayan fire had always been, but their cast-iron shot flew to pieces on the armor of the ironclads, which passed without serious damage. After passing the works they continued straight on, past more batteries, at Timbó, to Tayi. The batteries at Timbó were water batteries, and injured the ironclads more than all the others they had passed. In this passage one of the Brazilian monitors received no less than one hundred and eighty shot; and another one was hit one hundred and twenty times. Their plates were dented and bent, and the bolts started, but there was little or no loss of life on board them. If one or two of the Brazilian ironclads had remained between Humáitá and Timbó, instead of all running by the latter place, the works of the former would have been really closely invested; and as the object of running the batteries was to cause the surrender of Humáitá, the movement was to that extent a failure. The Paraguayans evacuated their works at their leisure, taking guns and stores. THE RIVER FIGHT AT TAYI. Twice, in the year 1868, the Paraguayans attacked the Brazilian monitors lying off Tayi, just above the influx of the river Bermejo. These desperate attacks showed the most heroic bravery and devotion, but were never successful. Upon one occasion the iron-clad vessels Lima-Barros and Cabral were attacked, and on another the Barroso and the monitor Rio Grande. After the last attack, in July, the Brazilians threw a boom across the stream, which would detain their enemies, descending in their canoes, long enough to give time for preparation. These Paraguayan boats were admirably adapted for navigating those waters, where there was a rapid current and many sand-bars, constantly shifting, with channels, more or less deep, between them. The canoes were built so that only a part of the central section was borne by the water, and they were consequently easily turned, while they glided over the water, propelled by spoon-shaped paddles. Some of these craft were very large, and would carry a cargo of many tons.