roof the vessel had been swept clean of everything that shot could cut down-railings, stanchions, smoke-stack, steam-pipes, davits, flagstaff, one anchor, all gone; the muzzles of two of her guns were shot off, and her ram was broken off and remained in the side of the Cumberland. When it appeared that the Congress could not be obtained as a prize because she was under the fire of the shore batteries, she was set on fire with hot shot and burned to the water's edge. Part of the ship's company had been taken off in boats, and the others swam ashore.

Three Confederate gunboats, known as the James River Squadron, came down to take part in the fight and attacked the Minnesota; but her superior gunnery drove them off after they had killed or wounded more than twenty of her crew. Yet she was aground and appeared to be the next victim; but night was approaching, the tide was at ebb, and the pilots refused to attempt taking the Merrimac down the middle channel. Therefore she went by the south channel and anchored off Sewell's Point, expecting to resume her destructive work in the morning, and send the remainder of the National fleet to the bottom.

But-the fact that the Confederates were constructing a formidable ironclad was no secret, and early in August, 1861, the United States Navy Department advertised for plans and offers for building ironclads. John Ericsson, who had invented the hot-air engine and other apparatus, had long considered the idea of an ironclad with its guns in a revolving turret. He had shown his plans for one to Napoleon III. in 1854, but received no encouragement. The same idea, in cruder form, had been published by Abraham Bloodgood in 1807, by a Scotchman named Gillespie about the same

time, and again by Theodore R. Timby, an American, in 1841. He also approached Napoleon III. with his invention, but had no more success than Ericsson. Meanwhile he had appealed to the United States Government, and received a little half-hearted encouragement, but none that helped him. In 1862, however, he obtained a patent for the idea of a revolving tower for guns, and thereafter a royalty was paid to him for every vessel that was built with such a tower.

Ericsson answered the Navy Department's advertisement with his plan for such an ironclad, and after he had appeared before a board appointed for the purpose and demonstrated the practicability of his plan it was accepted, and he was ordered to proceed at once. He divided the work among three establishments, giving each full detailed drawings, and work was continued day and night. So well was it done that every part, as it arrived, fitted into its place without difficulty, and the vessel was launched at Greenpoint, Brooklyn, one hundred days after the laying of the keel. The inventor and builder named it Monitor. In a letter to the Assistant Secretary of the Navy he gave his reasons for the name: that batteries on the banks of Southern rivers could no longer prevent the entrance of Union forces; and that this new craft would give the British Lords of the Admiralty doubts as to the propriety of completing four very costly steel-clad ships which they had begun.

The Monitor was so constructed that its deck was but one foot above the water, on which it lay with the appearance of a raft. Rising from its centre was a round tower twenty feet in diameter and nine feet high, with ports for two guns, and between this and the bow was a square pilot-house made of solid blocks or logs of wrought iron nine inches thick and twelve inches

deep. Between the uppermost log and the one next below there was a narrow interval through which the pilot and the commander looked for their course and their antagonist. The vessel was built with an overhang all round, so that while the upper part was fortyone feet wide and one hundred and seventy-two feet long, the lower part (the hull proper) was but thirty-four by one hundred and twenty-two feet. She drew ten feet of water. Her two guns were eleven-inch columbiads, muzzle-loading. Her entire ship's company comprised fifty-seven men. The armour of the turret was made of eight plates, each one inch thick.

She left New York on the 6th of March, commanded by Captain John L. Worden, destined for Hampton Roads. Almost immediately orders were issued that she go instead to Washington; but though a swift tug was sent in chase, those orders did not reach her. After a difficult passage she arrived in Hampton Roads on the 8th (Saturday), where she found a dismal condition of affairs. The Cumberland was sunk, the Congress, set on fire by hot shot, was in flames, the Minnesota was aground, and everybody was dismayed. The Monitor was at once anchored near the Minnesota, the protection of which was her immediate task; and sailors were at work nearly all night putting shot and shell on board and making her ready for battle. When the Confederates saw her, they laughed at her small size and said "a cheese-box on a raft."

Soon after seven o'clock the next morning (Sunday) the Merrimac and the three gunboats came down toward the Minnesota with the intention of destroying her as they had destroyed the Cumberland and the Congress. But the Monitor steered straight for them, drove off the wooden gunboats, which fled upstream,