Regular meetings of the council shall be held at such times, not less than once in each month, as shall be prescribed by ordinance. Special meetings may be called by the mayor or acting mayor, on the written request of any three members of the council, specifying the object and purpose of such meeting, which request shall be read at the meeting, and entered at length on the journal. In all cases, it shall require a majority of the councilmen elect to constitute a quorum to do business; but a smaller number may adjourn from day to day, and may compel the attendance of absent members, in such manner and under such penalties as the council by ordinance may have previously prescribed.