and mercury, used for coloring images of plaster of Paris.
Potter's clay, from the Latin argilla; white clay.
A merchant-ship of the Mediterranean; specially of the Levant.
The term is now antiquated.
The battering-ram, so called because the metallic head of the beam was sometimes fashioned like the head of a ram. As a means of battering walls it is said to have been invented by Artemanes of Calzomene, a Greek architect, about 441 B. C. It is described by Josephus, who states that it was sometimes supported on the shoulders of men who advanced on a run; at other times it was slung from a frame, and operated by ropes.
Philip of Macedon is said to have been the first to place the frame on wheels, at the siege of Byzantium.
Plutarch informs us that Marc Antony, in the Parthian war, made use of an aries 80 feet long.
Vitruvius says they were sometimes 106 to 120 feet in length.
An instrument for a<
ore the invention of gunpowder, for making breaches in the walls of fortified places.
It consisted of a long pole or beam, with an iron head, suspended between uprights.
The head sometimes weighed a ton or more.
The men who operated it were protected by the testudo, a movable shed with a curved roof, adapted to resist the stones, etc., thrown on it by the besieged.
This machine is incorrectly stated to have been invented by Artemon, a Lacedemonian.
It was employed by Pericles, about 441 B. C. The pole was from 80 to 120 feet long, and suspended by cords on which it oscillated, being retracted by the united efforts of a number of men, who pulled the cords and then allowed the spar to swing forward and bring its armed head against the masonry of the besieged fortress.
Its effects were sought to be avoided by lowering down bags which acted as fenders to deaden the blow, by burning the framework, or by hurling missiles at the operators.
See descriptions of Roman military engines,