The choice of an umpire was entrusted to the king of Italy.
He is said to have acted as umpire during the dispute of Poseidon and Athena for the possession of Attica.
He's also a qualified hockey umpire in local leagues.
The umpire may be chosen by the arbitrators themselves or nominated by a neutral power.
Section 5 provides that where a reference is to be to a single arbitrator, and all the parties do not concur in appointing one, or an appointed arbitrator refuses to act or becomes incapable of acting, or where the parties or two arbitrators fail, when necessary, to appoint an umpire or third arbitrator, or such umpire or arbitrator when appointed refuses to act, or becomes incapable of acting, and the default is not rectified after seven clear days' notice, the court may supply the vacancy.