The tower over the crossing (see Fig. 894) is one of the most effective parts of the structure. It is about 30 feet square, and rises above the church as a square-angled structure, without buttresses or breaks. It has a lofty triple window in each face, each opening being crowned with a semicircular arch, and divided in the centre by an ornamental transom. On each side of the tower two niches, with carved canopies and corbels (but now without statues), occupy the plain space between the windows and the corners of the structure. Originally the tower was crowned with a canopy or spire of open work, similar to those which still exist at St. Giles’, Edinburgh, and King’s College, Aberdeen, and also that which formerly crowned the tower of Linlithgow Church. A slight corbelled break in the centre of each face of the tower indicates that a rib sprang from the centre of each face, as well as the angles of the tower, thus producing the effect of an octagonal crown, as at St. Giles’. Large picturesque gargoyles still break the line of the cornice on top. The whole church seems to have been designed and constructed at the same period--probably about the middle of the fifteenth century. The choir and nave were almost identical in their general features as originally executed; and the details of the piers, mouldings, bases, caps, &c., are very similar in both divisions. The style of the carved foliage is also similar in each, and bears the stamp of Scottish decorated work, but rather late in the style. As an indication that the building was completed about the middle of the fifteenth century, there occur in the “Buke of Auld Register of Haidinton”[174] many entries of gifts of chalices and other furnishings made to the various altars in the church, extending from 1423 to 1463, showing that “more than ordinary interest had been taken in the ‘Paroche Kirk.’” The altars were the following:-- 1. Our Lady Altar. 2. Haly Blude Altar. 3. St. Blaise’s Altar. 4. St. John’s Altar. 5. The Three Kings of Cologne. 6. St. Salvator’s Altar. 7. St. Katrine’s Altar. 8. St. Mychael’s Altar. 9. St. Towbart’s Altar. 10. Crispin and Crispianus. 11. Trinity Altar.[175] At the Reformation the possessions of the church and chapel dependent on it fell to Queen Mary’s brother, the Earl of Moray, who was Prior of St. Andrews. They were afterwards seized by the Earl of Morton, and, at his forfeiture, passed to the Crown. They were next presented by James VI. to his favourite, Esmé, Duke of Lennox, as a temporal lordship; and ultimately came into the hands of the Earl of Hopetoun.