The energy of the time was not, however, exhausted by the fervour of this outburst. The twelfth century took up and vigorously prosecuted the tasks handed on to it by the eleventh. Among cathedrals which were entirely, or almost entirely, rebuilt during this century we have Chichester, Rochester, Peterborough, Lincoln, Oxford, Bristol, Southwell, S. David's, Llandaff, and Ripon. In the first of these a great part of the work was done twice over within this period. Ralph de Luffa was bishop of the see when the cathedral was consecrated in 1108; two fires, however, did such serious damage to this building, the first in 1114, and the second in 1186, that it had practically to be re-constructed, and was re-dedicated in the year 1199. The Cathedral at Rochester was largely re-built by John of Canterbury between 1125 and 1137, and like Chichester suffered twice during the century from the ravages of fire. Indeed, so frequently do we find mention of conflagrations in the cathedrals in the early mediaeval days, that it is quite obvious that William I. was fully justified in taking such precautions against this enemy as the use of the curfew involved. In more than one instance the cathedral went up in flames as part only of a fire which destroyed a large portion of the town. [Illustration: SOUTHWELL MINSTER.] The undertaking of new work at Peterborough was the result of a similar cause. In the year 1116 fire destroyed almost the whole church and monastery, but in two years' time the re-erection had commenced, and was continued throughout the remainder of the century. The choir was ready for the resumption of the Divine offices in 1143, but the builders did not reach the end of their labours until 1237. Re-construction was necessitated at Lincoln by the occurrence of an earthquake in 1185, following once more upon a fire which took place in 1141. The stone vaulting and the western towers were undertaken by Alexander, bishop from 1123 to 1147; and in 1192 S. Hugh of Avalon, who held the see from 1186 to 1203, began a thorough re-building of the pile. This work marks an epoch in the progress of architecture in England, as in the choir of S. Hugh we meet with the earliest examples of the use of the lancet form of arch to which we can assign a known date. About the middle of this century a new church, not yet advanced to the dignity of a cathedral, was commenced at Oxford, and by the year 1180 it was sufficiently advanced to allow of the translation of the relics of S. Frideswide to their new shrine. In 1142 was founded the Abbey of Bristol, and its church was consecrated on Easter Day, 1148, although the completion of the buildings occupied the attention of the abbots for many years after. Southwell Minster was also building during the first half of the twelfth century; Peter de Leia, who became Bishop of S. David's in 1176, commenced the erection of his cathedral four years later, following the