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Symphonia caelestis Symphonia caelestis

by Giuseppe Severini

Published in:

Mediterranean Archaeology and Archaeometry, vol 18, n°4 (2018), pp.345-352

Gate of glory extrados statues represent the 24 elders of Apocalypse. They can also be symbols of Time (they are 24), Music (they bear musical instruments) and Divine harmony (they are heavenly creatures).

The two performers at the top are very close to Christ’s head, position as usual occupied by angels. If we compare them to the other musicians we observe they look to be the only two actually playing. The idea that a deeper symbolic significance could be discovered in this scene is strengthened by closer observation of the instrument features. A turning object, the wheel, creates the sound from strings stretched over a sound box made of two equal circles, to which an unusual keyboard is added, equipped with 11 keys, so that the octave is divided into 12 parts.
All this is strange enough and absolutely unique, in XII century at least !, and we need referring to any kind of theological, philosophical, mathematical and musical theory of the age to give a reasonable interpretation of it. Medieval Latin Platonism, for example, mainly related to Chartres cathedral school, well connected with Paris and Santiago, brings to us interesting suggestions.
Platonists thought that at the beginning of creation, making the World Soul, Demiurgos mixed three abstract elements: Being, Sameness and Difference. Having divided this compound into the right proportions of a Pythagorean diatonic scale he finally gave the World Soul the shape of two circles one inside the other and put them into the material World, thus creating both the Sphere of fixed stars and the plane of planetary orbits. Circular motions of planets and stars were thus connected in perfect harmony, like the strings of a well tuned Lyre or the pipes of a well cut Pan flute .
This set-up is reflected by our instrument.
A circular sound box, the Circle of Sameness, contains the wheel , symbol of planetary motion: the Circle of Difference. This is the origin: the invisible World Soul. Then another circle is added, the visible world, Cosmos, with its charming beauty. At last we find the keyboard, with 11 keys dividing the octave in parts, the symbol of human mind, which divides and measures in order to understand Natural phenomena. The vibrating string-length (rectilinear thought) is equal to the circumference of each circle of the sound box (Nature and abstract world).
Further suggestions come from the analysis of decorations.
A. A long line of DOTS runs all around the outline of the instrument. They are symbols of the stars. From left to right: first circle, the idea of the stars in the abstract world; second circle, the visible stars; keyboard, our knowledge of the stars (straightened).
B. The large ROSETTE in the middle represents the Visible World, a circular figure divided in four equal sections by two perpendicular axes. Each section is occupied by a five lobes leaf and twigs (these leaves are similar to those sculpted all around the 24 Elders). The division in four sections may refer to the four elements of material world.
This figure recalls diagrams of the seasons frequently drawn in glosses of IX-XII centuries astronomical manuscripts or even more elaborated drawings .

The main goal of any scholar was to calculate accurately the length of each season in order to obtain an exact and affordable calendar to establish with great accuracy both the dates of Christian feasts and the right hours for prayer in monasteries .

C.Finally, KEYBOARD LID decoration, unique among all other decorations sculpted in the Gate, shows a rare pattern, which had been popular in some areas around the Alps and in Ireland between IX and XI centuries, rather neglected in the XII .

Each knot of the interlace corresponds to one of the 11 keys protruding out of the rectangular box. This division in fact is the most puzzling feature of all, as nobody could justify the introduction of a chromatic scale in XII century musical practice, when only strict diatonism was allowed. But we discovered that, curiously enough, both the unusual decoration and the division of the octave in 12 semitones can be referred to diagrams of planetary latitudes, related to musical scales as well, in contemporary astronomical manuscripts.

Such diagrams were intended to describe planetary latitudes across the zodiacal band, divided vertically in 12 degrees. As usual the horizontal line of these grids was divided in 30 parts, but since XI century we often find 12 parts in order to signify the 12 zodiacal signs. The Sun and Saturn were given a serpentine path within the two middle degrees of the zodiac, Jupiter had three degrees, Mars four, Mercury eight, the Moon covered the zodiacal band with its 12 degrees of latitude. Venus was assigned a latitude of 14 degrees, one degree beyond the zodiac on each side.
Then, in a manuscript by Abbo de Fleury (c 940-1004) we find a horizontal column list of the Plinian intervals between planetary orbits attached to planetary latitudes grid .

Whether 14 semitones can be counted in total, the musical octave from Moon to Saturn is divided into 12 semitones (semitone being the unit of measurement of the scale, clearly enough). A keyboard with keys ranging about two full chromatic octaves demonstrates that this arrangement, despite the diatonic absolutism exhibited in sacred music, fits quite well XII century two voices polyphonic music, in original settings and in mutationes.

The middle key, the sixtht, indicates the Tritonus, in the middle of chromatic scale. Musician’s right hand is dangerously operating just aside.

In Santiago de Compostela doorgate one special music instrument looks like a summary of musica mundana main concepts, a retelling of the very ancient myth of Music of the Spheres. Symphonia could be its meaningful name instead of more popular Organistrum .

Letto 2779 volte Ultima modifica il Mercoledì, 13 Febbraio 2019 15:05

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