Shield.
1. (Weapon.) A portable defensive armor carried in front of the person. The ancient Greek shield, as described by Homer, was long enough to cover the man from the face to the knee. This was exceeded by the pavise of the Middle Ages, which was as tall as a man, and was carried by a pavisor, who therewith shielded an archer. It was also carried in assaults on fortifications. The Roman troops were drilled in modes of combining their shields so as to make a carapace, each soldier holding his shield aloft, the shields overlapping in such a manner as to glance off arrows and other missiles. It was called a testudo, from its resemblance to the back of a tortoise. The shield of the Roman legionary was of wood covered with leather, and studded with metal; it was 4 feet by 2 1/2. The shield of the ancient Briton was round and of basketwork. The Norman shield was kite or pear shaped. In the time of Edward IV. it had become triangular. In South Africa it is made of rhinoceros hide. The shield fell out of use when the broadsword was exchanged for the small sword and rapier. The introduction of fire-arms has farther changed the tactics, and the shield is a thing of the past with civilized nations. It would be a grateful accessory to the sharpshooter under some circumstances.
2. (Hydraulic Engineering.) The shield used by [2150] Brunel during the excavation of the Thames tunnel consisted of a strong iron framing, divided into compartments c c′ c′, within which the men worked. The top and bottom were formed of independent sections a a′ b b′, which were advanced alternately by means of jack-screws, and the front was protected by ranges of boards d d, which were separately removed to enable the men to excavate the mass of earth in front by small portions at a time, and then replaced as the sections advanced to secure the soft ground from pressing into the shield. The arch of brick was built in behind as the shield advanced.
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| Brunel's shield (Thames tunnel). |
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| Shield for corn in plowing. |
3. (Husbandry.) A fender-plate attached to the share of a corn-plow to keep clods from rolling on to the young plant.
