SKETCH 17 MEDALLION FROM RÜSTEM PASHA MOSQUE

Transcription

1 SKETCH 17 MEDLLION FROM RÜSTEM SH MOSUE The ornament on the window from Konya was quite different than all ornaments we have seen before the unusual shape of the star as well as the incredible accuracy of the construction make it very special. In the next example we will also deal with stars but the challenge will be different. This time we will go to the Rüstem asha Mosque. The Rüstem asha Mosque (Rüstem aşa Camii, 1560) in the Eminönü district over the Golden Horn is among the city's architectural gems. The mosque is famous for its extensive decoration with Iznik tiles. Our interest in this mosque will be quite different. We will look at the medallion at the minbar. In the center of the medallion there is one large ten-fold star and a maze of lines on the edge of the medallion. We already know how to create any star, but we will have to spend some time developing the edges of the ornament. Like in all ornaments using pentagons or decagons, we will have to concentrate on the part that we see without trying to extend it further on the plane. M e d a l l i o n f r o m R ü s t e m a s h a M o s q u e 1

2 Fig. 116 The minbar with an ornate medallion in the Rüstem asha Mosque The next photograph gives us much better view of the ornament on the medallion. Fig. 117 The medallion with the geometric ornament from Rüstem asha Mosque In the center of the ornament there is large ten-fold star with parallel edges of petals. The diameter of the star is about ½ of the diameter of the whole medallion. It is not exactly half, but we will correct it later. The lines of the edges of the petals extend towards the external part of the ornament. Finally on the border of the medallion we notice ten halves of stars with some edges wrapped mysteriously in a kind of bow. 2 u t h o r : M i r e k M a j e w s k i, s o u r c e h t t p : / / s y m m e t r i c a. w o r d p r e s s. c o m

3 Let us start construction of this complex ornament on the medallion. Fig. 118 Construction of the star for the medallion from the Rüstem asha Mosque STE 1: reparation Start by creating a segment, find its center O and draw a large circle with center in O and radius r= /2. Find the center of O, and use it to create a smaller circle with the center in O. Develop a regular dodecagon inscribed in the small circle. O STE 2: Creation of the first subgrid Extend each edge of the dodecagon in both directions. You will get part of the first subgrid. Use one of the methods we discussed before to find the point where the edges of petals of the star will cross (the large point in the drawing) Like we did many times before create a ten-fold star and extend its edges near tips of petals (thick lines). Extend edges of the petals in both directions (dashed lines). The first subgrid is complete. We have three families of parallel lines each family with four lines. This subgrid will be vital in creating the remaining part of the ornament. t the moment you already see what should be drawn further on this subgrid. M e d a l l i o n f r o m R ü s t e m a s h a M o s q u e 3

4 STE 3: Extending the ornament towards the edges of the medallion Use the subgrid to add petals of the stars on the edge of medallion. etween the central star and the external stars some small stars will be created. You can see them on my picture. STE 4: Creation of the second subgrid and extending the external stars The picture to the right is a zoom into one of the places where the external stars will be located. Draw another large circle with center on O and passing through point M. Find the two points and, as well as point S and draw two small circles with centers in and respectively, and radii equal to S or S. M X R U V W S T Y Find points R and T. These are points of the intersection of the small circles with the vertical subgrid lines. Draw lines U and U, and find points V and W. Create two kites by connecting points SVR and SWT. Extend edges of kites and use this new subgrid to draw segments ending in X and T Whatever we did for one star on the edge you will have now to repeat in your construction nine more times. The picture to the right shows how it may look. If you are using a computer program in this construction it would be useful to take the pattern that we created a while ago and rotate it 9 times about the center of the construction. If you are drawing it by hand, a template on a semitransparent paper could save a lot of work. Now is the time for a big cleaning, some final additions, and beautifying our construction. 4 u t h o r : M i r e k M a j e w s k i, s o u r c e h t t p : / / s y m m e t r i c a. w o r d p r e s s. c o m

5 Notice, in your construction there are still large empty spaces around points and. Fill them like it is shown here. oint U is the center of the segment TT. The rest is easy. elow I show two versions of the medallion. The left one is similar to the original on the minbar. The right one was filled with colors from the Rüstem asha Mosque. T Z T' CREDITS This document contains fragment of the first edition of my book Islamic Geometric atterns in Istanbul. The second, updated edition will be available in ll sketches were created using Geometer s Sketchpad, a computer program by KC Technologies, now part of the McGraw-Hill Education. More about Geometer s Sketchpad can be found at Geometer s Sketchpad Resource Center at ll rights reserved. No part of this document can be copied or reproduced without permission of the author and appropriate credits note. MIROSLW MJEWSKI, NEW YORK INSTITUTE OF TECHNOLOGY, COLLEGE OF RTS & SCIENCES, U DHI CMUS, UNITED R EMIRTES M e d a l l i o n f r o m R ü s t e m a s h a M o s q u e 5