Whenever damages on a motion are given, in the absence of any specific amount mentioned, the plaintiff will be entitled to recover twelve and one-half percent (12½%) on the whole amount, principal and interest, due at the time of the rendition of the judgment.
Code 1858, § 3592 (deriv. Acts 1835-1836, ch. 19, § 6); Shan., § 5357; Code 1932, § 9516; T.C.A. (orig. ed.), § 25-344.