ACTUARY. The name of actuarius, sc. scriba, in ancient Rome, was given to the clerks who recorded the Acta Publica of the senate, and also to the officers who kept the military accounts and enforced the due fulfilment of contracts for military supplies. In its English form the word has undergone a gradual limitation of meaning. At first it seems to have denoted any clerk or registrar; then more particularly the secretary and adviser of any joint-stock company, but especially of an insurance company; and it is now applied specifically to one who makes those calculations as to the probabilities of human life, on which the practice of life assurance and the valuation of reversionary interests, deferred annuities, &c., are based. The first mention of the word in law is in the Friendly Societies Act of 1819, where it is used in the vague sense, “actuaries, or persons skilled in calculation,” but it has received still further recognition in the Friendly Societies Act of 1875 and the Life Assurance Companies Act of 1870. The word has been used with precision since the establishment of the “Institute of Actuaries of Great Britain and Ireland” in 1848. The Quarterly Journal, Charter of Incorporation, and by-laws of this society may be usefully consulted for particulars as to the requirements for membership (see also Annuity). The registrar in the Lower House of Convocation is also called the actuary.