I.that which gives to any thing a downward pressure; weight, gravity.
I. Lit.: “plumbi,” Liv. 42, 63, 4.—
B. A fall, descent of water: “libramentum aquae,” Plin. 31, 6, 31, § 57: “quod libramentum cum exinanitum est, suscitat et elicit fontem, cum repletum, moratur et strangulat, of a spring that alternately rises and falls,” Plin. Ep. 4, 30, 10: “inferiore labro demisso ad libramentum modicae aquae receptae in fauces, palpitante ibi lingua ululatus elicitur, of the croaking of frogs,” Plin. 11, 37, 65, § 173.—
II. Transf.
A. A level surface, horizontal plane: extremitatem et quasi libramentum, in quo nulla omnino crassitudo sit, * Cic. Ac. 2, 36, 116: “sub eodem libramento stare,” Sen. Q. N. 1, 12, 1: usque ad libramentum summi fornicis, Ael. Gall. ap. Paul. ex Fest. p. 206 Müll.—
B. Evenness, equality: “ventorum hiemalium et aestivorum,” Col. 1, 5, 8—
C. A straight line: “si recto libramento inter solem terrasque media (luna) successit,” Sen. Ben. 5, 6, 4: “libramentum finale,” a boundary line, Amm. 15, 4, 4.—
D. A weight for balancing or giving motive power (ballista): “ferrea manus cum injecta prorae esset, gravique libramento plumbi recelleret ad solum,” Liv. 24, 34, 10: “arietem admotum nunc saxis ingentibus nunc libramento plumbi gravatum ad terram urguebant,” id. 42, 63, 4 Weissenb.: “late cladem intulisset, ni duo milites vincla ac libramenta tormento abscidissent,” Tac. H. 3, 23.