Said City is authorized and empowered to borrow money and issue its negotiable bonds and notes to an amount not exceeding $160,000, maturing, in installments as may be determined by the special committee authorized by section 64 of this chapter, within a maximum period of 30 years from date of issue, for the purpose of acquiring the necessary lands, easements, and sources of supply and constructing said water system and paying all expenses incident thereto. Such bonds shall bear interest at a rate not exceeding five percent and shall not be sold for less than 95 percent of their par value. The bonds or notes shall be signed by the Mayor of said City and countersigned by its Treasurer, and if interest coupons are attached they shall bear the facsimile signature of the Treasurer of said City. The bonds or notes shall specify on their face the purpose for which they are issued, and that they are issued under the authority of this subchapter, which shall be conclusive evidence of the liability of said City to any bona fide holder of the same. It is hereby made the duty of the said City to provide for the payment, and to pay the interest and principal, of said bonds or notes as they shall fall due. If said City shall for any cause fail to provide means for the payment of the interest and principal that may become due, then it shall become the duty of the City Council, without vote of the City, seasonably to assess upon the grand list of said City a tax sufficient to meet the interest and principal of said bonds or notes as they respectively become due, and place the same with a proper warrant, signed by a justice of the peace, in the hands of the Collector of Taxes for said City to collect the same immediately and pay it into the hands of the Treasurer, whose duty it shall be to pay the principal and interest of said bonds or notes as they shall fall due. Nothing contained in this section shall be construed to prohibit the holder or holders of said bonds or notes from resorting to any legal means to enforce payment of same.