Section 3. An election of such board of freeholders may be called at any time by the legislative authority of any such city. Such election shall be called by the chief executive officer of any such city within ten days after there shall have been filed with him a petition demanding such election, signed by a number of qualified electors residing within such city equal to twenty-five per centum of the total number of votes cast at the next preceding general municipal election. Such election shall be held not later than thirty days after the call therefor. At such election a vote shall be taken upon the question whether further proceedings toward adopting a charter shall be had in pursuance to the call, and unless a majority of the qualified electors voting thereon shall vote to proceed further, no further proceedings shall be had, and all proceedings up to the time of said election shall be of no effect.