The iron-clads employed by the United States on the Western rivers during the late civil war were mainly river steamers, the sides above the water-line placed at an
Wrought-iron bridges. angle of about 30°, and plated with 2 to 4 inches of iron, backed with 3 feet of oak. They carried 4 to 16 guns, and some of them were made to float in 2 1/2 feet of water.
They were calculated to fight bow on, and were practically invulnerable to 100-pound shot when in this position.
The Benton, Exsex, Carondelet, Lexington, and a large number of others, were of this construction.
Toward the latter part of the war a number of monitors were built for service on the Mississippi.
A class of vessels plated with 3/4-inch iron were jocularly called tin-clads.
Their armor was a protection against rifle-balls, but was easily penetrated by shells from the lightest field-pieces.
Improvised iron-clads, consisting of river steamers plated with railroad-iron, were used by both parties o
ted, and pressed together by passage between rollers.
The tarring-rollers rotate in fountain-troughs, and raise the contents into contact with the paper.
Hopper and movable gate.
Felt drawn over a roller in the bottom of the hopper.
Mixing vessel with steam-jacket and beaters.
Sand-box and movable apron for carrying along the materials.
Tank, sand and gravel box, and pressure-roller, so as to make the operation on the paper continuous.
Felt or paper placed on a bed, and the tarhopper moved over it, spreading the tar. Sand operation similar.
Fig. 4427 is a machine for forming sheet-metal plates into continuous strips for roofing, the strips being afterward joined together on the roof.
The ends of sheets or strips of metal are interlocked, and the metal then passed between rollers to close the seams, and then through a bath of molten tin or other soft metal, which coats the surfac