In this blog post, James Taylor, one of our Open Treasure Gallery Attendants, investigates why bronze was the material of choice when it came to the construction of Durham Cathedral’s famous Sanctuary Knocker.
The original 12th century Sanctuary Knocker, housed in the Great Kitchen in Open Treasure, is one of the most iconic images associated with Durham Cathedral. Made of bronze, it takes the form of a lion haloed by its mane, devouring a man whose legs are being eaten by snakes. The knocker is not just an important image associated with Durham, but is one of the foremost bronze sculptures to have emerged from Medieval Europe. So why was bronze chosen as the preferred medium for this impressive sculpture?
Practically, bronze is an inherently reproductive and versatile medium that can capture textures and forms to an astonishing degree. This was combined with the revival during the medieval period of the lost-wax casting technique. This allowed the construction of highly detailed, monumental pieces of bronze artwork such as the Sanctuary Knocker that would have been hard to produce in other materials.
A simplified version of the process would have involved the creation of an initial sculpture out of wax or clay that would have had a mould built around it. The initial object would be removed, allowing hot wax to be poured in recreating a hollow version of the original object. This would then be packed with san, before wax rods and a funnel were added to allow the flow of bronze and escape of gasses. A second mould would have been constructed around this model. The mould would then be placed in a kiln so that the wax could melt, before flowing out of the funnel. This would allow for the bronze to be poured into the mould and once cooled the mould would be broken apart, revealing the bronze sculpture within.
The casting process was also seen to have religious significance, making bronze an ideal material for such an important object. Those alive during the medieval era saw the process of creating bronze works through the lost-wax technique as equivalent to the creation process described in the Bible. Both Adam and Christ were made in the likeness of God, a process that evoked the idea of generating work through the casting method, in which an object is created as an exact likeness. Due to this association, bronze became a prized means of fashioning Christ’s likeness.
Not only was there a spiritual significance to the casting process, but bronze as a material was considered to contain mystical properties. We know this from two beautiful 13th century bronze door knockers on the south west door of Trier Cathedral in Germany. Cast into the knockers is the phrase “that which the wax gives, the fire removes and the bronze returns to you”. This very Tolkein-esque phrase describes the construction process of the knockers, whilst at the same time hinting at the mystic. Another knocker reads “Magister Nicholaus and Johannes of Bincio have made us”. They seem to be speaking directly to us. Is it possible that the use of bronze has instilled a sentience within the objects? This, combined with the reflective nature of bronze, and the fact that when light caught the glass eyes (which used to be fitted within the knocker) at certain angles, it may have seemed as if the knocker was alive and moving. A disconcerting prospect for anyone hoping to abuse the rights of sanctuary!
The revival of the lost-wax technique was not the only practice to return during the medieval period. The use of bronze for grand entrances to religious spaces harkened back to the classical practice of using bronze to signal a liminal transition between exterior and interior; between the sacred and secular realms. In Europe, this development often saw the creation of monumental bronze doors. For instance, that of the Bishop Bernward doors at the Cathedral of St. Mary at Hildesheim in Germany. Whilst Durham Cathedral does not have its own set of bronze doors, the fact that the North Door contains a considerable bronze sculpture, in the form of the replica of the sanctuary knocker, is enough to suggests that the monks of Durham Priory were aware of the significance of bronze as a material to mark the transition from the every day to the sacred.
Make sure to see the original Sanctuary Knocker, which is on permanent display within Open Treasure, when the cathedral and museum reopen to the public. But for now #StayHome, #StaySafe and enjoy these digital highlights!
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