The jurors so impaneled shall be sworn or shall affirm in substance as follows: “You do solemnly swear (or affirm) that you will well and truly ascertain and determine whether there is a public necessity for making the proposed improvement and for taking for the use or benefit of the public the private property which the petition describes and prays may be taken, and if you shall determine that it is necessary to make such improvement, and to take said property, that then you ascertain, determine and award the just compensation to be made therefor, and faithfully and impartially discharge all other duties as devolve upon you in this case, and unless discharged by the court, a true verdict give, according to the law and evidence, so help you God (or under the pains and penalties of perjury).” The jury shall hear the proofs and allegations of the parties, and shall go to the place of the intended improvement, in the charge of an officer, and upon or as near as practicable to the property proposed to be taken, and examine the premises. They shall be instructed as to their duties and the law of the case by the probate judge, and shall retire under the charge of an officer and render their verdict in the same manner as on the trial of an ordinary civil case, but the same shall be in writing and be signed by all jurors.