The Order has five officers: the Dean, the Chancellor, the Usher, the Lord Lyon King of Arms and the Secretary. The Dean is normally a cleric of the Church of Scotland. This office was not part of the original establishment, but was created in 1763 and joined to the office of Dean of the Chapel Royal. The two offices were separated in 1969. The office of Chancellor is mentioned and given custody of the seal of the Order in the 1687 statutes, but no-one was appointed to the position until 1913. The office has subsequently been held by one of the knights, though not necessarily the most senior. The Usher of the Order is the Gentleman Usher of the Green Rod (unlike his Garter equivalent, the Gentleman Usher of the Black Rod, he does not have another function assisting the House of Lords). The Lord Lyon King of Arms, head of the Scottish heraldic establishment, whose office predates his association with the Order, serves as King of Arms of the Order. The Lord Lyon often—but not invariably—also serves as the Secretary.