*104OPINION of the Court, by

Tli* appellants, onthe, 22d of January 1811, gave their obligation to pay, eighteen months after date, to John Watkins, agent of the penitentiary,» or his successor in of*105fice, the sum of S 150Ó, with interest on the whole sum for six months. The amount not being paid according to the stipulations of the obligation, the appellee brought suit in the court below, as the successor in office of John Watkins, and obtained a judgment for the amount thereof, with lawful interest from six months previous to the time of payment until paid.. To reverse this judgment the appellants have brought,the case to this court.

The objections to the sufficiency of the obligation can-, not be sustained. It plainly ánd obviously imports an Obligation to pay to John Watkins, for the benefit of the penitentiary institution. The , action we suppose Was properly brought by' the appellee* as the successor of Watkins, The law having created the office of agent* and provided for the appointment of an agent, and in case of a vacancy in that office having also farther provided for supplying that vacancy by farther appointments, must in Segal estimation he considered the creation of án officer with regular succession.

Tlie declaration contains substantially all necessary áfernieúts. It contains a sufficiency to shew the obligation was given for the use of the institution, and that the suit was brought by the appellee as the successor of the obligor in that character. The judgment correctly gavé interest for six calendar mouths before the note was páyable; for although time js in many instances computed according to lunar months, obligations should be construed according to the usual acceptation of the term used ; ánd it is believed according to the usual understanding, calendar months would be understood by expressions such as are used in the present obligation. According, however, to repeated decisions of this court, the rate of interest should háve been named in the judgment ; and because that Was not done, the judgment must be reversed. The case must be remanded to the court below, and judgment there entered for the debt in the obligation mentioned, with interest at the rate of six per centum per an mi from the period of six calendar months before the obligation became payable until paid, &c. The appellants must recover their costs in this court.