The series consists mainly of affidavits sworn in court or in the country before Commissioners of the Alienation Office as to the annual value of a property which was the subject of a conveyance in the Court of Common Pleas by means of a final concord or common recovery.
The intention was to ensure that the pre-fine, which was levied at a fixed proportion of the annual value, was not set too high. The affidavits were presumably sent to the office from the court.
The affidavits often provide detailed information about particular properties, which included not only lands but other hereditaments such as courts, markets and fisheries. They clarify exactly what a property consisted of, something which could be obscured by common form in other documents relating to the transaction, and can give information about the tenure and management of the property for some time previously, especially as the affidavit was often sworn by a bailiff or land agent.
The surviving affidavits survive only from some of the terms from 1802 to 1834.