The defendant may traverse the return on the writ for replevying the plaintiff and if it appears that he is not guilty of eloigning the plaintiff, he shall be discharged and recover costs; but if he does not traverse it, or if on such traverse it appears that the defendant did eloign the plaintiff, an alias writ of reprisal shall issue, substantially in the form heretofore established and used in the State, on which he shall be committed to jail to remain irrepleviable until he produces the body of the plaintiff or proves his death. He may suggest the plaintiff's death and the court shall impanel a jury to try the fact at the defendant's expense; and if the death is proved, he shall be discharged.