The Topkapı Scroll

A paper roll about thirty metres long filled with 114 drawings of geometric patterns (girih star patterns for walls and vaults, and plans of muqarnas), made as a pattern book for a Timurid or Turkmen architectural workshop. It is the most important surviving evidence of how Islamic geometric ornament was actually designed.

For most of the history of Islamic architecture there are no drawings: the builders’ methods have to be inferred from the buildings. The scroll kept in the library of the Topkapı Palace is the great exception. Its drawings are made in ink and colour on sheets of paper glued end to end, each pattern shown as a repeat unit or a panel; there is no text at all. It seems to have been carried to Istanbul among the booty or gifts of the early sixteenth century, and its style places it in the workshops of western Iran in the later fifteenth century.

What makes the scroll precious is that many drawings show not only the finished pattern but, in faint incised or dotted lines, the underlying construction: grids of polygons, circles and radial lines from which the visible strapwork was derived. A pattern is thus shown to be the result of a procedure, not a freehand invention: the procedure that this book models in the girih generator. Other sheets give the plans of muqarnas vaults, drawn as networks of simple cell shapes seen from below, from which a mason could build the three-dimensional vault tier by tier.

The scroll was published in full, with a long study of geometry and ornament in Islamic architecture, by Gülru Necipoğlu in 1995. It has since become central to the debate about how much mathematics Islamic craftsmen used: the drawings show that pattern-makers worked with repeat units, underlying polygonal grids and a small family of tile shapes, and that muqarnas were conceived in plan.

The book, part by part