If the United States shall determine to take lands, buildings or other property, necessary for the purposes mentioned in the first section¹ of this act, and cannot agree with the owner or owners of such lands, buildings or other property for the compensation to be made for such taking, the court of common pleas having jurisdiction in the county where such lands, buildings or other property is situated, shall, upon application by either the United States, or the owner or owners, or any one in behalf of either, appoint three disinterested freeholders, who, having duly qualified before said court, and having given such public notice and such notice to owners of the premises to be viewed and appraised of the time and place of meeting, as the said court may direct, shall ascertain and determine the amount of compensation to be paid to said owner or owners, and shall make reports to said court of their award, on or before the first day of the term next after their appointment: Provided, That the said United States shall not be authorized to take possession of or use or occupy the lands, buildings or other property taken under the provision of this section until the amount of said award shall be paid to the owner or owners thereof: Provided further, That the said court may set aside the report of said viewers, upon being satisfied that the amount of said award is excessive or insufficient: And provided further, That, upon the application of any party aggrieved, made within thirty days after the filing of the report of the viewers, for an issue to try the facts in controversy between the respective parties and to determine the amount of compensation due for property condemned and taken or for property injured or destroyed by the construction or enlargement of the works and improvements contemplated by this act, it shall be the duty of said court to award said issue, and any appeal taken pursuant to this act, shall be signed by the party or parties taking the same, or by his or their agent or attorney, and shall be accompanied by an affidavit of the party appellant, or by his or their agent or attorney, that the same is not taken for the purpose of delay, but because the affiant firmly believes that injustice has been done.