Now it is known that João de Castilho was working at Alcobaça in 1519. In 1522 he was busy at Belem, where he may have been since 1517, when for the first time some progress seems to have been made with the building there. What really happened, therefore, may be that when he left Thomar, the Coro was indeed built, and the eastern buttresses finished, but that the carving of the western part was still uncut and so may have been the work of Ayres after João was himself gone.[116] This is, of course, only a conjecture, for Ayres seems to be mentioned in no document, but whoever it was who carved these buttresses and windows was a man of extraordinary originality, and almost mad fancy. To turn now from the question of the builder to the building itself. The large round buttresses at the west end are fluted at the bottom; at about half their height comes a band of carving about six feet deep seeming to represent a mass of large ropes ending in tasselled fringes or possibly of roots. On one buttress a large chain binds these together, on the others a strap and buckle--probably the Order of the Garter given to Dom Manoel by Henry VII. Above this five large knotty tree-trunks or branches of coral grow up the buttresses uniting in rough trefoiled heads at the top, and having statues between them--Dom Affonso Henriques, [Illustration: FIG. 55. THOMAR. CONVENT OF CHRIST. S. DOOR.] [Illustration: FIG. 56. THOMAR. OUTSIDE OF W. WINDOW OF CHAPTER HOUSE UNDER HIGH CHOIR IN NAVE.] Dom Gualdim Paes, Dom Diniz and Dom Manoel--two on each buttress. Then the buttress becomes eight-sided and smaller, and, surrounded by five thick growths, of which not a square inch is unworked and whose pinnacles are covered with carving, rises with many a strange moulding to a high round pinnacle bearing the cross of the order--a sign, if one may take the coral and the trees to be symbolical of the distant seas crossed and of the new lands visited, of the supreme control exercised by the order over all missions. Coral-like mouldings too run round the western windows on both north and south sides, and at the bottom these are bound together with basket work.