The Cosmati Pavement in Westminster Abbey

The extraordinary pavement in front of the high altar at Westminster Abbey was installed starting in 1268. The fascinating design has an overall fourfold symmetry and certain elements repeat, but on the other hand every part of the design is unique. The men who did the work came from Rome. This sort of abstract tiling was a Roman specialty, called in the west of Europe "Cosmati" after one of the leading families in the business. The supervisor of this project was named Odoricus, about whom hardly anything is known.

The stones and glass that make up the pavement look quite different in different lights, so it is hard to say what color anything actually is; compare these two to get some idea of the different photographs available.

A Latin inscription that once decorated the floor reads:

In the year of Christ one thousand two hundred and twelve plus sixty minus four, the third King Henry, the city, Odoricus and the abbot put these porphyry stones together.

If the reader wisely considers all that is laid down, he will find here the end of the primum mobile; a hedge (lives for) three years, add dogs and horses and men, stags and ravens, eagles, enormous whales, the world: each one following triples the years of the one before.

The spherical globe here shows the archetypal macrocosm.

Why the strange arithmetic of the date?

It is usually suggested that 1212 plus 60 equals 1272, the date of Henry III’s death, and 60 minus 4 equals 56, the length of his reign. It would seem therefore that the inscriptions were added shortly after his death.

The abbey's web site continues:

The abbot mentioned was Richard de Ware, who was buried beneath the pavement. Richard Sporley, a medieval monk of Westminster, wrote “The primum mobile means this world, whose age or ending the writer estimates, as he imagines it, by increasing the numbers three-fold”. So a hedge lives three years, a dog nine, a horse twenty seven, a man eighty one and so on. The final date is calculated by a chronology based on the mythical life-spans of animals. And he explains that the macrocosm is “the great world in which we live”, the microcosm being man. The ‘spherical globe’, he says, is “the round stone, having in itself the colours of the four elements, fire, air, water and earth”. According to the only medieval interpretation we have, the pavement thus symbolises the world, or the universe, and its end.

If that is right, our Odoricus was not one to shy away from the most important themes in his work.

These designs were considered almost magical by the patrons who paid for them, because they involved complex geometry such as very few people in thirteenth-century Europe could understand. This technique was called opus sectile or "cut work." Whereas in a traditional mosaic all of the pieces were of about the same size and shape, in these works each piece was cut to a special design. The pavement measures 24 feet 10 inches (modern style), which was 25 medieval Roman feet (7.58 m). According to the abbey's web site:

The central roundel is made of onyx and the pavement also includes purple porphyry, green serpentine and yellow limestone. Also part of the original material are pieces of opaque coloured glass – red, turquoise, cobalt blue and bluish white. It lies on a bed of dark limestone known as Purbeck marble. . . . The design consists of a broad border with a rectangle in the middle of each side and five roundels between each rectangle. The border encloses another square set transversely with its corners pointing north, south, east and west. Between the inner border and the transverse square are four triangular spaces occupied by large roundels. Within the transverse square is a pattern known as a quincunx, with a large roundel in the very centre flanked by four roundels as if in orbit around the centre. The basic layout is a four-fold symmetry, but in detail the variations are endless. No two roundels are the same. Of the four ‘orbiting’ roundels one is circular, one hexagonal, one heptagonal and one octagonal. The infill patterns are all different. 

The pavement was recently restored at great expense, and the abbey's web site has a series of videos documenting the process. The cleaning and repair made a huge difference in how the pavement looks. Above is the before shot of one small section, below the after. (Although, again the light makes a big difference.)

The pavement is a great wonder, and I am thrilled that it has been conserved and repaired so that it may last another 750 years.