No doubt the early part of the fifteenth century was the period when the cathedral was most glorious within and without. Fuller, in his "Church History," published in 1655, from which quotation has already been made, after giving an account of the building of the cathedral, says: "But now in the time of the aforesaid William Heyworth, the Cathedral of Litchfield was in the verticall height thereof, being (though not augmented in the essentials) beautified in the ornamentals thereof. Indeed, the West front thereof is a stately Fabrick, adorned with exquisite imagerie, which I suspect our age is so far from being able to imitate the workmanship that it understandeth not the Historie thereof. Surely what Charles the Fifth is said to have said of the citie of Florence, that it is a pittie it should be seen save only on Holy-dayes; as also that it was fit that so fair a Citie should have a Case and Cover for it to keep it from wind and weather, so in some sort, this Fabrick may seem to deserve a shelter to secure it. But alas! it is now in a pittiful case--indeed, almost beaten down to the ground in our civil dissensions. Now, lest the Church should follow the Castle--I mean quite vanish out of view--I have, at the cost of my worthy friend here exemplified the Portraiture thereof; and am glad to hear it to be the design of ingenious persons to preserve ancient churches in the like nature (whereof many are done in this, and more expected in the next part of Monasticon), seeing when their substance is gone, their verie shadows will be acceptable to posteritie." In the fifteenth century a library was built outside the door of the north transept, but a little to the west; it was quite separate from the cathedral. This was one of the gifts of Dean Heywood (1457-1493). It is recorded that he gave £40 towards the building of it, but died before it was completed, and this was done by his successor, Dean Yotton, who also contributed to its erection. According to the statement in "_Anglia Sacra_" it was finished in the year 1500. It is marked in the plan of Browne Willis, 1727, and was taken down about 1750. Some time in this century saw a change in the tracery of many of the windows. It may be that the introduction of printing was responsible for this change, and that the greater amount of light admitted by the windows of the Perpendicular style made their insertion advisable; or it may be that the tracery of windows being naturally fragile, in many cases a renewal became necessary, and the new Gothic style was naturally considered the best. Whatever the reason, the new Perpendicular tracery was inserted in many of the windows just as it was in a large number of cathedrals and churches all over England.