The regular meetings of the common council shall be on the first Monday night in each month, and at such times as may be deemed necessary for the transaction of the business of said city, and shall be held at such place in said city as the common council shall from time to time ordain and appoint; and said common council shall meet in special session upon the call of said mayor or upon the call of any two of the councilmen. And the common council shall by ordinance prescribe the mode in which notice of special meetings shall be given; and no business shall be transacted at such special meetings unless a majority of all the members of the common council shall be present, except that a less number may compel the attendance of absent members under such reasonable penalties as they may think proper to impose; and all questions put, except in such matters as are hereinafter provided for, shall be decided by a majority of the members present.