There is hereby continued the fund known as the "sinking fund of the city of New York" which shall have for its purpose the amortization and redemption of the principal of the debt of the city of New York incurred on and after the first day of January eighteen hundred ninety-eight, and evidenced by corporate stock of the city of New York, excepting that issued to provide for the supply of water and that issued since the first day of January, nineteen hundred ten, for rapid transit or rapid transit unification purposes and that issued since the first day of July nineteen hundred eighty-one which is redeemable from the general sinking fund or any other sinking fund established pursuant to sections two hundred ninety through two hundred ninety-nine.