In this state the church remained until the last quarter of the thirteenth century, a building handsome and interesting, but not specially remarkable for size, and without any peculiar or unique feature. Its western doorway may have opened straight upon what was then, it appears, the market-place of the town. The commercial prosperity of the place, its trade in wool, were growing; and we are justified in supposing that the merchants of the town took their part in the great extension of their parish church. This extension was no mere result of the fact that Grantham was a lordship belonging to the Crown; nor, we may be sure, did the Dean and Chapter of Salisbury undertake the gratuitous task of enlarging to nearly double its size a church which represented to them a portion of their income, and would certainly never occur to them in the light of a cherished possession demanding expensive care. But to the men of the town it was a cherished possession; and the greater part of the cost was doubtless supplied by merchants, the fathers and kinsfolk of the Haryngtons and Saltebys who founded chantries in the next century within its walls. But the mother church at Salisbury helped to supply at any rate some of the ideas to which the townsmen’s money-gifts gave shape. Her chapter-house was finished somewhere between 1270 and 1280, and the cusped circles in the heads of the windows of the north aisle at Grantham, the shafted mullions with plainly moulded caps and bases, are accurate reminiscences of its simple and beautiful geometrical tracery. Lincoln, too, where, in 1280, the great eastern chapel—the so-called “Angel Quire,” built to contain St. Hugh’s shrine—had been consecrated, supplied its share: the west window of the north aisle at Grantham is an ingenious adaptation to six lights, with a slight improvement, of the eight-light east window at Lincoln. These, however, are merely details by which the work at Grantham may be assigned to the year 1280 or a little later. The design of the masons included a western extension of the church, accompanied by a widening of the aisles, and, with this, the building of a western tower.