| The Vault as Illusion (5) |
Whether the next set of patterns were produced in response to these "Acts of God" or because the masons were now "into" tiercerons, ribs started multiplying at an alarming rate. At the simplest level, you can now admire the greatest tierceron vault ever made, at Exeter Cathedral. Probably begun sometime after the split ribs at neighbouring Bristol and Wells, Exeter's vault has the thickest ribs, the biggest bosses, and the most tiercerons—and also happens to be the longest stone vault in the world, at 350 ft. That ought to do the trick!
If you like, you can believe that Gloucester cathedral had additional forces to contain. At about the time Ely suffered its Act of God, someone murdered the King of England in truly grisly fashion. The abbot of Gloucester immediately got him sainted and did up the choir of his cathedral as a tourist-attraction shrine (very successful, too). So Gloucester not only has God to contend with, but the Ghost of a murdered king. Better take extra precautions?
The vault of the choir at Gloucester is fiendishly complex to look at. Tiercerons, liernes (mini tie-in ribs) and bosses all over the shop. So start by looking at the animated diagram on the right, which will explain the structure and concept. Basically, the masons have woven a second set of tierceron patterns through the first to double the number of tierceron "ropes". Then they tripled the ridge rib. Easy, really.
Now you may admire the vault itself, where a myriad additional liernes completely jazzle the eyes. In fact, the masons also roped in the help of the heavenly host, members of which appear on some of the bosses. Nothing left to chance, here.
A more widespread response seems easier on the eye but it sets off a new set of illusions. It involves tripling the ridge ribs and compacting each bay by shifting the diagonal ribs to connect with the tiercerons further down. This reduces the width of each bay and surrounds the central point with four new intersections, giving the visual effect of increased strength. On the right an animated diagram shows you how it worked.
This pattern was used in the nave at Winchester, and also in Ely's troublesome 46-foot wide Lady Chapel (begun before the tower fell, and vaulted afterwards). Notice how the extra ridge ribs are broken up into liernes that zigzag around and start to redefine your perception of the vault. Because liernes have no visual "root" at the spring of the vault, they appear to cling to its surface, rather than to define its shape. So now you look more at the volume of the vault, rather than its lines.
Just to remind you, the ribs, and therefore also the liernes, serve no structural function. They are just there to confuse and delight the eye. All these vaults get called lierne vaults because of all those extra liernes, but don't let that fool you. Each one is still the same old domed-up groin vault structure.
The vault at Canterbury is surprisingly conservative. It's a plain tierceron with tripled the ridge ribs broken into zigzagging liernes. Simpler design. Similar effect on your perception. This is the latest vault, and the plainness of its design clearly implies it's no fun when God won't play.
But now (page 6), the most beautiful vaults ever devised! Well, can you be surprised? Their patterns clearly imply that they were created with the help of God Himself.
Page 1: structure and terms
Page 2: an idea is born
Page 3: the patterns and the power
Page 4: problems with towers
Page 5: the masons fight back
Page 6: lilies, seashells, snowflakes and waterfalls
Page 7:
| Why Use Stained Glass? | Classical Beauty | Before Stained Glass | Seeking the Perfect Vault | The Vault as Illusion |