The object of these curved cones, with their projecting horns, may be explained as follows:--It will be seen on referring to the Plan (see Fig. 1070) that the centre line of the east chapels is not in the centre of the space between the two eastmost buttresses, and consequently not in line with the centre of the north and south windows between those buttresses. In order to make the centre line of the vaulting coincide with the centre of the windows, it was necessary to introduce some kind of support for the foot of the east arches, at a distance of about 2 or 3 feet from the east wall. The above cones and horns were introduced for this purpose, and from them the vaulting on the east side springs. In connection with this arrangement, the late David Roberts, R.A., contended that the “east wall of Rosslyn had been pulled down and set further back, to give 3 feet more room.”[85] But this supposition finds no warrant whatever from an examination of the building. A more likely explanation is that the above cones may have been introduced as a kind of imitation of the springing of [Illustration: FIG. 1083.--The Collegiate Church of Rosslyn. Eastern Chapels.] the fan vaulting common in England in the fifteenth century. The heavy pendants were also probably derived from the same source. Against the east wall of the choir were the remains of four altars, which have been restored (see Fig. 1083), one of them being situated over the stair leading to the lower chapel. Beside it there is a square headed piscina, and on the south side of the other altars there are ogee headed recesses in the wall. On the east side of the south doorway there is a richly carved stoup. In the transepts (Fig. 1084) there are remains of three canopied piscinas, two in the south transept and one in the north transept. They bear a general resemblance in their details to the sacrament houses in some of the churches in the north, and to the piscinas in Melrose Abbey. Between the two in the south transept there is a recess in the wall, showing where an altar has been intended, and a similar indication in the north transept on the north side of the piscina shows the same intention. Over each of these altars there are three moulded and carved brackets, probably meant for statues. On the south side of the centre opening into the choir there is a recess for another altar, and on the north side there is an arched piscina; both have carved brackets above them. A bracket in a similar position, relative to the altar and piscina, exists at Dunglass Church.