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An Imaginary Gothic Cathedral being built around 1312, say France. Typically at the time because of Financial Constraints, or building Failure, the Construction time could take 100 to 200 years. If there were no problems during the construction period, an acceptable time frame would have been 60 to 70 years.
These buildings were commissioned by the Bishop of the Church in a particular Area, but the reality is the Chapter, (a group of Clergymen) controlled Finance and would in conjunction with the Bishop, hire the Master Builder (Architect, Engineer and Builder all rolled into one package).
The Master Builder Designed, Supervised and hired and fired the Master Craftsmen
who would work under him.
Each Master Craftsman ran a workshop for his own particular trade, each had many apprentices or assistants, who would one day become one hoped, a master themselves. Heavy work was done by labourers, generally unskilled and from the surrounding countryside.
The Master Builder would spend several weeks planning, sketching and costing, and would eventually settle on a final design. The final Designs were drawn on sheets of plaster and presented to the Bishop and Chapter for approval. Typically a Floor plan and an Elevation to the top most vault.
Possible Wall Design
At the same time the Master Quarryman with 50 apprentices, and 250 labourers would depart to the local limestone quarry.
Labourers would assist the stone cutters lift large pieces of stone out of the quarry, at which time it was cut, chiselled, and hammered to patterns or templates supplied by the Master Mason. Each stone was marked three times, once to show it's future location in the Cathedral, once to show which quarry it came from (this was a wages for the Quarryman thing), and once to show which stone cutter had actually cut the stone, (this was a wages for the Stonecutter thing).
The site for the Cathedral would be cleared, and the location of the Apse and Choir marked out with wooden stakes. All workshops would be built where craftsmen could eat, rest and work in bad weather. Forges were built for the production of tools and nails, and Labourers would begin to dig the hole for the foundation. Foundations were made of thick walls, built 7.6 metres (25 feet) below ground level. This supported the building and prevented it from settling unevenly.
During this time the roof timbers, some 18.3 metres (60 feet) long would be arriving from Scandinavia, and the local timber and stone arrive to be taken to the site and stored.
After the completion of the foundation hole for the Apse and Choir, the Bishop would bless the first foundation stone as it was lowered into the bed of small stones covering the clay at the bottom of the excavation.
The mortar men would be ready with exact mixtures of sand, lime and water. Labourers carried the mortar down ladders to the masons who would lay the stones on top of each other, trowelling a layer of mortar between each stone and each layer of stones.
The Master mason would continually check with his level to make sure the stones
were perfectly horizontal and with his plumb line to make sure that the wall was
When the foundations were complete, work began on the walls. The walls of a Gothic Cathedral consist of piers or columns that support the vault and roof, and the space between the piers that is filled for the most part with the tracery; the stone framework of the windows; and small areas of solid wall construction. The piers of the choir would be 50 metres (160 feet) high and 1.8 x 2.4 metres (6 x 8 feet) thick. They were constructed of hundreds of pieces of cut stone. The tracery, all of which was cut from templates, was hoisted into place as the piers were being built.
For the small area of solid wall the stone mason would actually construct two parallel walls of cut stone. Then, using a piece of wood or chain as reinforcement, he would fill the space between them with concrete, a mixture of mortar and small stones. It would have been too expensive to build walls of solid stone.
The Master Builder knew that buttresses had to be built to relieve the pressure the vault would place on the piers. These buttresses, erected on foundations next to the piers, would later be connected to the piers themselves by stone arches, known as 'Flying Buttresses'. In Gothic Cathedrals the arched vault tended to push the piers outward. This force was transferred through the flying buttress to the buttress itself and then down to the foundation. In this way the main piers could remain quite thin in proportion to their height, allowing more space for the windows between them.
As the walls grew higher wooden scaffolding became a necessity. The scaffolding was made of poles lashed together with rope. Hoists were attached to it so that the stones and mortar could be lifted. The scaffolds also held work platforms for the masons made of mats of woven twigs. They were called hurdles and could be easily moved.
Since long pieces of wood were both difficult to find and expensive, the scaffolding for the walls above the arcade did not reach to the floor or ground. It was hung from the walls and lifted as construction progressed. Ladders were not necessary to reach it, as several permanent spiral staircases were built into the wall itself.
To build the flying buttresses it was first necessary to construct temporary wooden frames called Centering. These would support the weight of the stones and maintain the shape of the arch until the mortar was dry.
These centering were first built on the ground by the carpenters, then they were hoisted into place and fastened to the pier at one end and to the buttress at the other. They acted as temporary flying buttresses until the stone arch was complete.
In November, as in every winter, the finished stonework was covered with straw and dung to prevent the frost from cracking the mortar before it had completely dried. Most of the masons went home for the winter because mortar work cannot be done in cold weather. Other work continued, however, for temporary workshops were built against the finished walls of the choir to house the stone cutters, who could no longer work outside. There they cut stones and tracery, carved capitals, and sculptures in preparation for the return of the masons in the spring.
The walls of the choir were constructed in three stages. First was the arcade of piers that rose 24 metres (80 feet) from the foundation. Above them was the triforium, a row of arches that went up another 6 metres (20 feet) in front of a narrow passageway. And the last stage was the clerestory, which consisted of 18 metre (60 feet) windows that reached right up to the roof.
The roof was made up of a series of triangular frames or trusses. The carpenters first assembled each individual truss on the ground. The timbers were fastened together by the mortice-and-tenon method; holes called mortices were cut, into which the tongues or tenons of the other pieces would then fit. After test assembling every part the truss was dismantled and hoisted piece by piece to the top of the walls.
Once at the top it was reassembled and the entire frame was locked together with
oak pegs. Nails were not used by the carpenters in the construction of the roof
While this was happening, on the ground, the roofers were casting lead sheets that would cover the wooden frame, protecting it and the vaults from bad weather. They also cast the drain pipes and gutters. The stone cutters and sculptors carved the stone gutters and spouts that were to be installed in the buttresses. These down spouts, through which the water from the roof fell to the ground, were carved to look like frightening creatures. They were called gargoyles and, when it rained, they would appear to be spitting water onto the ground below.
The gargoyles were installed on the buttresses and connected to the gutters at the base of the roof by a channel along the top of the flying buttresses. Then large vats of pitch were hoisted up to the roof and the timber was coated to prevent it from rotting. Finally, as the sheets of lead were nailed to the framework, the edges were rolled to prevent any water from seeping in.
After about 28 years the choir would have been ready for the construction of the vaulted ceiling and the foundation of the transept to begin. It could also be at this time that the original Master Builder, now getting on in years, be replaced by his First Apprentice or another Master builder.
Two devices were used to lift the stones and concrete to the roof for the construction of the vaults. The first was the windlass and the second was the great wheel. The windlass, which had helped lift the timbers to the roof, was already in place and was used to raise the great wheel.
The wheel was large enough so that one or two men could stand inside. Through its centre ran a long axle to which the hoisting rope was fastened. As the men walked forward both the wheel and the axle turned, winding up the rope. This method enabled them to lift very heavy loads.
In order to construct the vaulted ceiling a wooden scaffold was erected connecting the two walls of the choir 40 metres (130 feet) above ground. On the scaffolding wooden centerings like those used for the flying buttresses were installed.
These would support the arched stone ribs until the mortar was dry, at which time the ribs would support themselves. The ribs carried the webbing, which was the ceiling itself. The vaults were constructed one bay at a time, a bay being the rectangular area between four piers.
Finally the keystone was lowered into place to lock the ribs together at the crown, the highest point of the arch.
Two teams, each with a mason and a carpenter, worked simultaneously from both sides of a vault - installing first the lagging and then the webbing.
When they met in the centre the vault was complete. The vaulting over the aisle was constructed in the same way and at the same time.
When the mortar in the webbing had set, a 100mm (4 inch) layer of concrete was poured over the entire vault to prevent any cracking between the stones. Once the concrete had set, the lagging was removed and the centering was lowered and moved onto the scaffolding of the next bay. This procedure was repeated until, eventually the entire choir was vaulted.
At a foundry four large bells would be cast in Bronze. A model of the bell, as if it were solid, was first made of clay and plaster of Paris. It was covered then with a coat of wax of the same thickness that the finished bell was to be, and the required decoration on the outside of the bell was carved on the wax. This was then covered by a layer of clay and plaster compound.
When the whole construction was heated the wax melted and ran out, leaving a cavity between the outer shell and the core. This was the mould into which molten bronze was poured. When the metal cooled the mould was destroyed and the bell was prepared for shipment to the building.
A heavy timber framework would be constructed in the North Tower. From it the bells were carefully hoisted and fastened into place. Four ropes would hang down from the bells. When they were pulled the bells would rock back and forth, causing the hammers inside to hit the sides of the bells. The ringing would be heard for miles.
After say 80 years the Carpenters and roofers would have completed work on the spire, which rose above the crossing of the nave and the transept. The spire was a wood frame structure covered with sheets of lead and highly decorated with sculptures and ornaments.
Glazing and Doors
While the Windows were being installed, plasterers covered the underside of the vault and painted red lines on it to give the impression that all the stones of the web were exactly the same size. They were eager for the web to appear perfect, even if no one could see the lines from the floor.
After 80 years work would be in progress on the west end or front of the Cathedral. The construction of the towers would be supervised by the Current Master Builder. Master Builders were prone to being replaced at times through their untimely deaths from scaffold falls etc.
While the Glass was being installed externally the Stone cutters and Sculptors finished the mouldings and capitals while masons laid the stone slabs that made up the floor. They created a maze pattern in the floor. Finding one's way to the centre of the maze was considered as worthy of God's blessing as making the long pilgrimage through the countryside that so many would have to do in order to worship in the completed Cathedral.
The stone mullions of the rose window for the front of the cathedral were carefully cut according to the plans. Voussoirs were carved to form the arched gables over each of the three front doors and a tympanum - a semicircular sculptured panel - was carved to go above each of the doors.
The Masons put together the pieces of the rose window and installed the tympanums and voussoirs over the doors. Then the window makers came and filled the rose window's 9.5 metre (32 feet) diameter with hundreds of pieces of coloured glass.
Meanwhile, in the carpenters' workshop the Entry Doors were being built. The centre door alone was almost 7.6 metres (25 feet) high, made of heavy planks of wood and joined with cross-ribs. A Blacksmith made all the nails for the door and a Master metal worker made the bolts, locks and hinges.
After say 86 years the last pieces of the sculpture would have been hoisted into their niches. The Cathedral was finished. The current Bishop and the chapter would led a great procession through the narrow streets, returning to the grand, new Cathedral with the entire population of the city for a service of thanksgiving.
Huge coloured banners would be hung from the triforium, and all the candles on the piers would be lit. The choir would sing, and the Cathedral would be filled with beautiful sounds and the people, most of them grandchildren of the men who had laid the foundation, would be filled with tremendous awe and joy. For 86 years the townspeople had shared one goal and it had at last been reached.