The order of condemnation, upon the payment of the sum ascertained and assessed by the verdict of the jury, or the deposit thereof in the court for the defendant, shall vest in the United States the title in fee simple to the lands to be acquired for the uses and purposes stated in the application. But if an appeal shall be taken by either party, then the United States or its agents, upon the deposit in the court for the party whose land is sought to be condemned of the amount of damages and compensation so assessed, together with the cost of the proceeding, and giving a bond in double the amount of damages assessed, shall be entitled to enter upon the land so condemned and survey, construct and operate on the same for the uses, and purposes stated in the application, but such easement shall not vest absolutely in the United States until the final determination of the cause and payment or deposit in court of such damages and compensation as shall then be adjudged.