§ 72. Sinking fund. Unless under special laws governing the city at
the time this chapter takes effect provision is made for the creation or
maintenance of a sinking fund or funds for any purpose, thirty per
centum of all moneys or revenues received by any city which has term
bonds outstanding and unpaid, or by any officer, board or department
thereof, from any source other than taxes or loans shall, upon receipt
of the same, be forthwith deposited in a separate account or accounts in
one or more of the designated fiscal depositories of the city to the
credit of the bonded indebtedness of the city, and said deposit shall be
known as the sinking fund. The sinking fund shall be used exclusively
for the payment, as it matures, of the principal of the indebtedness of
the city evidenced by term bonds other than bonds issued for
improvements financed by assessments for benefit or bonds issued prior
to the effective date of the local finance law, in anticipation of the
collection of revenues. If, under the special laws governing the city at
the time this chapter takes effect, provision is made for the creation
or maintenance of a sinking fund or funds for any purpose, such sinking
fund or funds shall continue and be maintained as provided in such laws.