This northern transept seems to have been a favourite spot for interments; for during the excavations numerous skulls were found there. At Clairvaux, the corresponding site was strewn with the graves of bishops, who selected it as the place wherein to rest after life's weary struggle. No record or memorial of these survives, or of any of the dead interred at Mellifont, to point out the occupant of a single grave. In the northern wall of this transept is a beautiful door-way with jambs of clustered columns. Hard by, the wall was pierced to make a loop-hole when Mellifont was transformed into a fortress. On one side of the door-way are the remains of what must once have been a superb chapel; on the opposite side are a few steps of a spiral stair-case, formed in the thickness of the wall, which led up to the tower, as is to be seen at Graignamanagh, Co. Kilkenny, and other houses of the order in Ireland. The level of the floor here is some five or six feet lower than the adjacent road-way which was raised by the accumulated rubbish of former buildings that extended along the hill-side where the cottages now stand. The southern transept may have had its six altars also. The aisle seems to have been built up, and when the alterations which took place in the whole fabric in the fifteenth century were made, a large portion of this transept would appear to have been allocated to the uses of a sacristy. No trace of a sacristy remains elsewhere, and this would be a very convenient place to utilise as one. The remains of some walls lead us to suppose such an arrangement probable. In Cistercian monasteries, a stair-case in this transept near the cloister led thence to the dormitory, but no remains of such a stairs have been discovered at Mellifont. When Sir Thomas Deane had the earth and rubbish, or, as he calls it, the "grassy mound," removed, he discovered the foundations of two semi-circular chapels in each transept, in a line with the site occupied by the High, or principal Altar. (See the dotted lines in the Ground Plan). Describing them, Sir Thomas writes: "Within the circuit of the external walls are the foundations of an earlier church which indicate four semicircular chapels, and two square ones between. Of this church we have no distinct record, but the bases of semi-detached pillars would indicate the date given for the erection of Mellifont." These four semi-circular chapels in line with the High Altar, formed an exact counterpart of the church of Clairvaux which was erected in 1135, and which by St. Bernard's express wish, served St. Malachy as the model for Mellifont.