Sec. 50. The introduction of more light, however, was not the only reason for the rebuilding and heightening of aisles. The east end of an aisle, as has been said, provided a convenient place for one of the side altars of the church. This was the case even in the narrow aisles of the twelfth and thirteenth century, many of which, like the north aisle of Great Easton church in Leicestershire, provided with a drain, aumbry, or a corbel for a statue, bear witness to the existence of a contemporary altar. At Harringworth in Northamptonshire there had been an aisleless church, to which a tower had been added at the end of the twelfth, and aisles early in the thirteenth century. On 24 October 1305 Edward I granted letters patent to William la Zouche, by which he had licence to assign a certain amount of land to two chantry chaplains in the chapel of All Saints. This may have been his private chapel, but was possibly in the church. A little earlier than this, to judge by the character of the architecture, a new north aisle had been built, with a new altar at the east end. Very soon after the granting of the licence, it would appear that the whole of the south arcade was taken down, and a new south aisle and arcade built. The work was done in a very conservative spirit, for the old thirteenth century porch and inner doorway were rebuilt on the new site, and an old string-course was re-used internally, beneath the new windows. The piscina and the three sedilia, which belonged to the altar at the end of the aisle, remain in the south wall, and there are corbels for statues on either side of the east window. However, rebuilding did not stop here; for it seems that, during the next few years, the north arcade was entirely rebuilt so as nearly to match that on the south. Thus the work, beginning with the north aisle, and extending over some thirty or forty years, finished on the side on which it began. Numerous examples of a closely parallel kind, fortified by documentary evidence, might be given. [Illustration: Fig. 12. Plans of Grantham church: (1) probable arrangement about 1190; (2) at beginning of 14th century.]