The stockholders, each of whom shall be entitled to 1 vote for each share of stock held by him, may elect from their number a board of trustees of not less than 6 nor more than 15 members, a majority of whom shall constitute a quorum, and the trustees shall appoint from their own number a president, secretary and treasurer, who shall perform the duties of their respective offices in accordance with the rules and regulations which may be prescribed by the board of trustees.