In Norman, then, and early English, the single lights north and south, set forth the Apostles and Doctors who have shined forth in their time as the lights of the Church: and the rich pattern of flowerwork wherewith the stained glass in them was decked, represented the variety of graces in each. But to have symbolised the servants without the Master, the members without the Head, had been at variance with all the Catholic Church has ever practised. Looking therefore to the east end, we behold that well-known feature, the Triplet: setting {xci} forth the Most Holy and Undivided Trinity. [Footnote 58] Nor is this all: to denote that all the Church has, and all She is, is from above, the string course, springing from the eastern triplet, runs round the whole church (often both within and without,) binding it, as it were, in and connecting every other light, with those at the east. Again, the Western Door, as we shall see, symbolised Christ: and two lights, typical of His two natures, are therefore generally placed over it. There are, undoubtedly, instances of western triplets: though we think that the Camden Society has well explained these. [Footnote 58: We read, in the legend of S. Barbara, that, being confined by her father in a room where were two windows only, she added a third, by way of setting forth this Mystery.] In some cases, there is a series of couplets on each side of the church: and, taking the hint from Durandus, we may interpret this arrangement of the mission of the Apostles two and two. A series of triplets as in Salisbury cathedral, and the Lady Chapel of Bristol, is very rare: and, of course, not objectionable on any other grounds than that of the too cheap use of a most beautiful feature. So far all is simple: but as we approach the decorated style, the symbolism becomes excessively complicated. The principal doctrines of the Catholic Church are set forth in each window: and to unravel the whole of these is often a task of no small difficulty. We shall proceed to give a few examples, with the explanation which appears to us probable: entreating the reader to remember, that if in any instance our conjectures should appear unfounded, the failure of probability in one case throws no discredit on the others, and still less does it invalidate the system. Durandus's silence on the language of tracery is easily explained by the consideration, that assign as late a date as we will to the {xcii} publication of his work, it came forth while the Early English style was yet in existence: and his silence on triplets only proves, what is well known to ecclesiologists, that they are far less common in foreign than in our own architecture.