The year of the fall of the tower--1220--was also that in which the body of St. Thomas, the martyred primate of Canterbury, was translated from the crypt of Canterbury Cathedral to the choir. St. David’s, in common with many other great churches, determined to dedicate a chapel to his memory. In 1329 this chapel was probably remodelled, when Sir R. Symonds gave his manor of St. Dogmell to secure two chaplains to celebrate daily mass for his soul and his wife’s at the altar of St. Thomas. It has the only original completed Decorated vaulting in the building (except the south porch), and two stages were added above, making the building taller than the transept and giving the remarkable external effect seen from the north-east. The chapel has served as a chapter-house, library, and vestry, and on its south side has a very beautiful double piscina, in character purely Early English. The trefoiled heads are characteristically moulded and the spandrils richly carved, one with stiff-leaved foliage, another with a bird and foliage, and the third represents a fight between a man and a devil which is trying to devour another man. This piscina is interesting, apart from its beauty, as showing that the Early English architects could work purely in that style when they desired, and that in all probability their use of Transitional detail was prompted by their artistic sense and desire to make their work harmonise with their predecessors’. The vaulting rises from octagonal shafts with round flowered caps, and the bosses at the crossing of the ribs are elaborate. One contains the head of our Lord, and another a similar subject, but the Head censed by angels. The storey above was the original =Chapter House=, later the Grammar School, now the =Library=. This position is, we think, unique for a chapter-house. It is very plain and has a mediæval recessed closet; also a fine Decorated fireplace (and in it a most unworthy stove), which is obviously the work of Gower, as it is almost precisely similar to one in the residential part of his palace over the river. There are also some Early English bracket capitals, one foliated and the other with the nail-head, probably to carry lights. On the cill of the north window is a fragment from the old organ-case, showing how well it was worthy of being, at any rate, attributed to Grinling Gibbons. The room above this (third stage) was used as the Treasury, but is not of any great interest. Scott did away with an unsightly temporary wooden stair leading to the chapter-house from the transept, and re-used the original entrance from the north choir aisle; but we do not consider the present arrangement very satisfactory, as it still has a temporary appearance.