CURTIUS, MARCUS, a legendary hero of ancient Rome. It is said that in 362 B.C. a deep gulf opened in the forum, which the seers declared would never close until Rome’s most valuable possession was thrown into it. Then Curtius, a youth of noble family, recognizing that nothing was more precious than a brave citizen, leaped, fully armed and on horseback, into the chasm, which immediately closed again. The spot was afterwards covered by a marsh called the Lacus Curtius. Two other explanations of the name Lacus Curtius are given: (1) a Sabine general, Mettius (or Mettus) Curtius, hard pressed by the Romans under Romulus, leaped into a swamp which covered the valley afterwards occupied by the forum, and barely escaped with his life; (2) in 445 B.C. the spot was struck by lightning, and enclosed as sacred by the consul, Gaius Curtius. It was marked by an altar which was removed to make room for the games in celebration of Caesar’s funeral (Pliny, Nat. Hist. xv. 77), but restored by Augustus (cf. Ovid, Fasti, vi. 403), in whose time there was apparently nothing but a dry well. The altar seems to have been restored early in the 4th century A.D. In April 1904, on the N. side of the Via Sacra and 20 ft. N.W. of the Equus Domitiani, remains of the buildings were discovered.
See Livy i. 12, vii. 6; Dion Halic. ii. 42; Varro, De lingua Latina, v. 148; Ch. Hülsen, The Roman Forum (Eng. trans. of 2nd ed., J. B. Carter, 1906); O. Gilbert, Geschichte und Topographie der Stadt Rom im Altertum, i. (1883), 334-338.
CURTIUS RUFUS, QUINTUS, biographer of Alexander the Great. Of his personal history nothing is known, nor can his date be fixed with certainty. Modern authorities regard him as a rhetorician who flourished during the reign of Claudius (A.D. 41-54). His work (De Rebus gestis Alexandri Magni) originally consisted of ten books, of which the first two are entirely lost, and the remaining eight are incomplete. Although the work is uncritical, and shows the author’s ignorance of geography, chronology and military matters, it is written in a picturesque style.
There are numerous editions: (text) T. Vogel (1889), P. H. Damste (1897), E. Hedicke (1908); (with notes), T. Vogel (1885 and later), M. Croiset (1885), H. W. Reich (1895), C. Lebaigue (1900), T. Stangl (1902). There is an English translation by P. Pratt (1821). See S. Dosson, Étude sur Quinte-Curce, sa vie, et ses œuvres (1887) a valuable work; F. von Schwarz, Alexander des Grossen Feldzüge in Turkestan (1893), a commentary on Arrian and Curtius based upon the author’s personal knowledge of the topography; C. Wachsmuth, Einleitung in das Studium der alten Geschichte (1895), p. 574, cf. p. 567, note 2; Schwarz, “Curtius Rufus” No. 31 in Pauly-Wissowa (1901).
CURULE (Lat. currus, “chariot”), in Roman antiquities, the epithet applied to the chair of office, sella curulis, used by the “curule” or highest magistrates and also by the emperors. This chair seems to have been originally placed in the magistrate’s chariot (hence the name). It was inlaid with ivory or in some cases made of it, had curved legs but no back, and could be folded up like a camp-stool. In English the word is used in the general sense of “official.” (See [Consul], [Praetor] and [Aedile].)
CURVE (Lat. curvus, bent), a word commonly meaning a shape represented by a line bending continuously out of the straight without making an angle, but only properly to be defined in its geometrical sense in the terms set out below. This subject is treated here from an historical point of view, for the purpose of showing how the different leading ideas were successively arrived at and developed.
1. A curve is a line, or continuous singly infinite system of points. We consider in the first instance, and chiefly, a plane curve described according to a law. Such a curve may be regarded geometrically as actually described, or kinematically as in the course of description by the motion of a point; in the former point of view, it is the locus of all the points which satisfy a given condition; in the latter, it is the locus of a point moving subject to a given condition. Thus the most simple and earliest known curve, the circle, is the locus of all the points at a given distance from a fixed centre, or else the locus of a point moving so as to be always at a given distance from a fixed centre. (The straight line and the point are not for the moment regarded as curves.)