It shall be a misdemeanor for any officer or agent of any such corporation to exact from any employee more than twelve hours' labor within the twenty-four hours of the natural day, and within twelve consecutive hours therein as in section 34:10-3 of this title provided. In case of accident or unexpected contingency demanding more than the usual service by the corporation to the public, or from its employees to the corporation, extra labor may be permitted and exacted for extra compensation.
N.J.S. § 34:10-4