§ 204. Agreements for payment of cost of construction by instalments. The department, board or officer having control of such public parks may agree with the person or corporation with whom any contract may be made for the construction, equipment and operation of said railroad that the cost of such construction shall be paid by such cities in instalments out of the compensation which such person or corporation shall agree to pay to such cities under any such contract from time to time as such compensation shall be received.