The clerk of the county commissioners had no authority by law to receive the petition for an assessment of damages against the railroad corporation. Such petition must either be made to the county commissioners in regular session, under the Rev. Sts. c. 39, §§ 56 seq., or to the commissioners or their chairman, under St. 1839, c. 76, §§ 2, 3. The filing of a petition with the clerk was not such an application as the law requires. This was settled in Eaton v. Framingham, 6 Cush. 245. The petition not having been duly filed with the commissioners until after the expiration of three years from the filing of the location of the railroad, the commissioners had no authority to assess damages under the petition. They acted wholly without jurisdiction. Charlestown Branch Railroad v County Commissioners, 7 Met. 78. Writ of certiorari to issue.