Said board of commissioners shall meet at least once every week in regular meeting in the city hall, at such time as shall be fixed by said board of commissioners, and take under advisement and act upon such business as may come before them. A majority of the members of said board shall constitute a quorum for the transaction of business, but no final action shall be taken in any matter respecting the department of any absent commissioner unless such business has been made a special order, with notice to such commissioner of such contemplated action, or unless such action is taken at a regular meeting of the board.