Article IV.—The sole questions excepted from the provisions of the preceding article are those which, in the judgment of any one of the nations involved in the controversy, may imperil its independence. In which case, for such nation, arbitration shall be optional; but it shall be obligatory upon the adversary power.
Article V.—All controversies or differences, with the exception stated in Article IV., whether pending or hereafter arising, shall be submitted to arbitration, even though they may have originated in occurrences ante-dating the present treaty.
Article VI.—No question shall be revived by virtue of this treaty concerning which a definite agreement shall already have been reached. In such cases arbitration shall be resorted to only for the settlement of questions concerning the validity, interpretation, or enforcement of such agreements.
Article VII.—Any Government may serve in the capacity of arbitrator which maintains friendly relations with the nation opposed to the one selecting it. The office of arbitrator may also be entrusted to tribunals of justice, to scientific bodies, to public officials, or to private individuals, whether citizens or not of the States selecting them.
Article VIII.—The court of arbitration may consist of one or more persons. If of one person, he shall be selected jointly by the nations concerned. If of several persons, their selection may be jointly made by the nations concerned. Should no choice be made, each nation claiming a distinct interest in the question at issue shall have the right to appoint one arbitrator on its own behalf.
Article IX.—When the court shall consist of an even number of arbitrators, the nations concerned shall appoint an umpire, who shall decide all questions upon which the arbitrators may disagree. If the nations interested fail to agree in the selection of an umpire, such umpire shall be selected by the arbitrators already appointed.
Article X.—The appointment of an umpire, and his acceptance, shall take place before the arbitrators enter upon the hearing of the question in dispute.
Article XI.—The umpire shall not act as a member of the court, but his duties and powers shall be limited to the decision of questions upon which the arbitrators shall be unable to agree.
Article XII.—Should any arbitrator, or an umpire, be prevented from serving by reason of death, resignation, or other cause, such arbitrator or umpire shall be replaced by a substitute to be selected in the same manner in which the original arbitrator or umpire shall have been chosen.
Article XIII.—The court shall hold its sessions at such place as the parties in interest may agree upon, and in case of disagreement or failure to name a place the court itself may determine the location.