Vadas József (szerk.): Ars Decorativa 13. (Budapest, 1993)
SIPOS Enikő: Arányok és mértékek. A magyar koronázási palást struktúrája
the proportion theory typical of that age, and how it was applied in practice. The theory of proportions describes a meaning of mathematical relations between different parts of an object. The Medieval theory of proportions is described by Panofsky as schematic; when defining the measurements of the parts it did not use fractions but a system of measures or moduls. The measurements of a body in plane, for example, were described in face lengths. The total length of the body usually took nine face-length units. The Byzantine theory of proportions was quite consistent, even the details of the head were defined in a modul system, with the length of the nose as the basic unit. Reducing the horizontal and vertical measurements of the head to a single unit offered a single method that clearly shows the medieval tendency to use schematic systems in plane geometry. With this method measurements and even shapes could be defined in a geometrical way. If the all horzontal and vertical measurements of the head can be defined as multiples of the same unit - in this case, the length of the nose -, the entire configuration can be defined by three concentric circles, with the origo on the root of the nose. The "three-circle scheme" was fairly popular in Byzantium and Byzantine arts, as well as in Austria, Germany, France and Italy. 5 In fact, the medieval theory of proportions meant a kind of numeric system of measures, built on one single modul, which used counting, where the given modul or unit could be multipled or divided. Thus, knowing a section of a given length - which could be either the side of a square, the radius of a circle, the side of a regular polygone or a nose-length - the work of art can be prepared in any amplification or reduction according to scale. 6 It is enough, therefore, to give only one measure of a geometrical figure - in this case the side of the square - and every further steps will be related to this unit; the proportions between the sections remain the same. The basis of the planning was obviously the square and the circle, since the entire construction was easy to make in the simplest way, with the help of a compass or a string fixed in the origo. All important points - including the exact place and measurements of the cross, the mandorlas, the dividing stripes and the medallions were defined by circles drawn in or around the squares, giving also the basic process of planning, the sequence of the related steps. We presumed that in the case of the mantle the basic modul must have been the side of a square. Its length is equal to the radius of the semicircle where the row of pictures situated. As the first step of the construction, the section was marked; when doubled, it gave the exact diameter of the semicircle, which was probably one fathom, i.e. 310 cms. From the time of King Stephen, the Hungarian royal system of length measures originated from Carolingian Bavaria. One fathom was ten feet. A fathom of the same length was used in the Bavarian court, where it was called fathom or "rod". In metrical units, it was 310 cms. 7 This is the diameter of the mantle. Dividing the modul by two, we get a pair of squares half the size of the previous one. Repeating the operation for a few times we get five pairs of square on both sides of the middle line, with all the related concentric circle sections. Construction was started from the outside towards the centre, i.e. from the bigger to the smaller units, because it was always easier and more exact to divide a big unit than to multiple a smaller one. The construction process was the following:
