In the channel, at the mouth of the Mississippi, were heavy mud banks, made of deposits brought down by the stream. To take the large vessels over this bar was Captain Farragut's first great task. The water was so shallow that the keels of the ships would sometimes stick in the mud, and then it was with the greatest of difficulty that they could be hauled off.
It was the 18th of April before all the vessels were in the river and ready to attack the forts; and in the meanwhile, a great naval battle had been fought in other waters.
The Confederates had captured the Norfolk navy yard, and with it the United States vessel Merrimac, which was there at the time. They removed the masts of this vessel, and then fitted her with an iron prow, and built sloping sides over the deck, covering them with iron rails laid closely together side by side.
Five of the best Northern war vessels lay in the bay outside of the harbor.
On March 8th, 1862, the Merrimac attacked this fleet. She drove her iron prow straight through the side of the Cumberland. This vessel sank almost immediately, and but few of the men were saved.
Then the Merrimac attacked the Congress, drove her ashore, and set her on fire with red hot shot. Meanwhile, broadside after broadside had been fired at the Merrimac; but the shot bounded harmlessly from her sloping iron sides.
Night came on, and before attempting to destroy the other three ships, the black monster waited for the daylight.
There was consternation all through the North. How could a stop be made to this fearful work of the Merrimac? There was no telling what she might do on the morrow.
That same night there steamed into Chesapeake Bay a queer looking little vessel which had been built by a famous mechanic, Captain John Ericsson. She was named the Monitor. She had a low, flat deck, pointed at both ends. In the center was a round, revolving turret. The vessel was completely plated over with iron, and in the turret were two enormous guns, larger than any that had ever been used before.
