Calceus (calx, the heel). A shoe or boot made sufficiently high to completely cover the foot. The Romans put off their shoes at table; hence calceos poscere meant “to rise from table.”
Calculus (dimin. of calx, a small stone or counter). A pebble, or small stone worn by friction to present the appearance of a pebble. Calculi were used in antiquity for recording votes (for which purpose they were thrown into the urn), for reckoning, and for mosaic paving (hence the English word “calculation”).
Caldarium (calidus, warm). The apartment in a set of Roman baths which was used as a kind of sweating-room. This chamber, which is constructed nearly always on the same plan in the different baths which have been discovered, included a Laconicum, a Labrum, a Sudatorium, and an Alveus. (See these words.) Fig. [56] (on p. [32]) represents a portion of the caldarium of Pompeii, restored.
Caldas Porcelain is from the Portuguese factory of that name, specialized for faiences in relief; the greater number are covered with a black coating; the others with the customary enamels of the country, violet, yellow, and green.
Caldron, for domestic use of the 14th century, is depicted as a tripod with a globular body, and broad mouth and two handles.
Calibre (or Caliper) Compasses. Compasses made with arched legs.
Caliga. A military boot worn by Roman soldiers and officers of inferior rank. The caliga consisted of a strong sole, studded with heavy pointed nails, and bound on by a network of leather thongs, which covered the heel and the foot as high as the ankle.
Caliptra. (See Calyptra.)
Caliver. A harquebus of a standard “calibre,” introduced during the reign of Queen Elizabeth.
Calix. A cup-shaped vase, used as a drinking-goblet. It was of circular shape, had two handles, and was mounted on a tolerably high stand. The term also denotes a water-meter, or copper tube of a specified diameter, which was attached like a kind of branch-pipe to a main one.