Section 62. Unless the parties in interest agree as provided in section sixty-one, upon application of the county commissioners, the department, the department of highways, the board of aldermen, the selectmen or the directors of the railroad corporation or of the railway company for the appointment of such commission, the superior court shall cause notice thereof to be given to the other parties interested fourteen days at least before the time fixed for the hearing; and thereupon, after hearing, shall appoint such commission, one member of which shall be a member of and designated by the department. The commission shall meet as soon as may be after its appointment, and, after notice to and a hearing of the parties, shall make a written award and return it to said court.