§ 1933. When county clerk or register to discharge mortgage of record. The county clerk, upon being furnished with an order discharging a mortgage of record, as provided in section 1931 or section 1932, and, in the city of New York, the register, upon being furnished with a certified copy of such order, and upon payment of the fees allowed by law for discharging mortgages, shall record the order and discharge the mortgage of record.