The plan of the whole building is most unusual and original: the nave is a circle some seventy-two feet in diameter, surmounted by a dome, and surrounded by eight shallow chapels, of which one contains the entrance and another is prolonged to form a narrow chancel. This chancel leads to a larger square choir behind the high altar, and east of it is a round cloister sixty-five feet across. The various monastic buildings are grouped round the choir and cloister, leaving the round nave standing free. The outside of the circle is two stories in height, divided by a plain cornice carried round the pilasters which mark the recessed chapels within. The face of the wall above this cornice is set a little back, and the pilaster strips are carried up a short distance to form a kind of pedestal, and are then set back with a volute and obelisk masking the offset. The main cornice has two large corbels to each bay, and carries a picturesque balustrading within which rises a tile roof covering the dome and crowned by a small lantern at the top. The west door has two Ionic columns on each side; a curious niche with corbelled sides rises above it to the lower cornice; and the church is lit by a square-headed window pierced through the upper part of each bay. Only the pilasters, cornices, door and window dressings are of granite ashlar, all the rest being of rubble plastered and whitewashed. [Illustration: PLAN OF NOSSA SENHORA DO PILAR] Now the eucalyptus-trees planted round the church have grown so tall that only the parapet can be seen rising above the tree-tops. Though much of the detail of the outside is far from being classical or correct, the whole is well proportioned and well put together, but the same cannot be said of the inside. Pilasters of inordinate height have been seen in some of the Lisbon churches, but compared with these which here stand in couples between the chapels they are short and well proportioned. These pilasters, which are quite seventeen diameters high, have for capitals coarse copies of those in São Vicente de Fora in Lisbon. In São Vicente the cornice was carried on corbels crossing the frieze, and so was continuous and unbroken. Here all the lower mouldings of the cornice are carried round the corbels and the pilasters so that only the two upper are continuous, an arrangement which is anything but an improvement. Another unpleasing feature are the three niches which, with hideous painted figures, are placed one above the other between the pilasters. The chancel arch reaches up to the main cornice, but those of the door and chapel recesses are low enough to leave room for the windows. The dome is divided into panels of various shapes by broad flat ribs with coarse mouldings. The chancel and choir beyond have barrel vaults divided into simple square panels.