Section 118 - Investigations by commissioner1. The commissioner may, of his own motion, investigate or make inquiry, in a manner to be determined by him as to any act or thing done or omitted to be done by any common carrier, subject to his supervision, and the commissioner must make such inquiry in regard to any act or thing done or omitted to be done by any such common carrier in violation of law or an order of the commissioner.2. Complaints may be made to the commissioner by any person or corporation aggrieved, by petition or complaint in writing setting forth any thing or act done or omitted to be done by any common carrier in violation, or claimed to be in violation, or of the terms and conditions of its franchise or charter or of any order of the commissioner. Upon the presentation of such a complaint the commissioner shall cause a copy thereof to be forwarded to the person or carrier complained of, which may be accompanied by an order, directed to such person or carrier, requiring that the matters complained of be satisfied, or that the charges be answered in writing within a time to be specified by the commissioner. If the person or carrier complained of shall make reparation for any injury alleged and shall cease to commit, or to permit, the violation of law, franchise or order charged in the complaint, and shall notify the commissioner of that fact before the time allowed for answer, the commissioner need take no further action upon the charges. If, however, the charges contained in such petition be not thus satisfied, and it shall appear to the commissioner that there are reasonable grounds therefor, he shall investigate such charges in such manner and by such means as he shall deem proper, and take such action within his powers as the facts justify.3. Whenever the commissioner shall investigate any matter complained of by any person or corporation aggrieved by any act or omission of a common carrier under this section it shall be his duty to make and file an order either dismissing the petition or complaint or directing the common carrier complained of to satisfy the cause of complaint in whole or to the extent which the commissioner may specify and require.