Maintenance and investment of sinking fund

(1) The municipality shall maintain a sinking fund for the repayment of money borrowed on debentures issued and shall pay by quarterly instalments into such sinking fund and such sum as will be sufficient for the payment within the period fixed for the loan of all monies borrowed on debentures issued. (2) All monies paid into the sinking fund shall be invested and applied by the Commissioner in such manner as may be prescribed.