Space Structures Their Harmony and Counterpoint Polyhedral Fancy designed by Arthur L. Loeb In the permanent collection of Smith College, Northampton, Massachusetts Space Structures Their Harmony and Counterpoint Arthur L. Loeb Department of Visual and Environmental Studies Carpenter Center for the Visual Arts Harvard University With a Foreword by Cyril Stanley Smith A Pro Scientia Viva TItle Springer Science+Business Media, LLC Arthur L. Loeb Department ofVisual and Environmental Studies Carpenter Center for the Visual Arts Harvard University Cambridge, MA 02138 First printing, JanlNJry 1976 Second printing, July 1976 1hird printing, May 1977 Fourth printing, May 1984 Fifth printing, revised, November 1991 Library of Congress Cataloging-in-Publication Data Loeb, Arthur L. (Arthur Lee) Spaee struetures, their hannony and eounterpoint / Arthur L. Loeb :with a foreword by Cyril Stanley Smith p. em. - (Design scienee collection) "A Pro scientia viva title:' Includes bibliographical references and index. ISBN 978-1-4612-6759-1 ISBN 978-1-4612-0437-4 (eBook) DOI 10.1007/978-1-4612-0437-4 1. Polyhedra. 1. Title Il. Series. QA491.L63 1991 516:15-dc20 91-31216 CIP American Mathematieal Society (MOS) Subject Classification Scheme (1970): 05C30, 10805, IOE05, 10ElO, 50A05, 50AlO, 50B30, 50005, 7OC05, 7OClO, 98A15, 98A35 Printed on aeid-free paper. Copyright © 1991 by Arthur L. Loeb. Originally published by Birkhăuser Boston in 1991 Copyright is not claimed for works of U. S. Government employees. AII rights reserved. No part of this publieation may be reproduced, stored in a retrieval system or transmitted, in any fonn or by any means, electronic, mechanical, photocopying, recording or otherwise, without prior permission of the copyright owner. Permission to photoeopy for intemal or personal use, or the intemal or personal use of specificc lients, is granted by Springer Science+Business Media, LLC, for Iibraries and other users registered with the Copyright Clearance Center (CCC) , provided that the base fee of $0.00 per copy, plus $0.20 per page is paid directly to CCC, 21 Congress Street, Salem, MA 01970, U.S.A. Special requests should be addressed directly to Springer Science+Business Media, LLC. ISBN 978-1-4612-6759-1 9 8 7 6 5 432 1 To the Philomorphs, Fellows in the Search for Order Design Science Collection Series Editor Arthur L. Loeb Department of Visual and Environmental Studies Carpenter Center for the Visual Arts Harvard University Amy C. Edmondson A Fuller Explanation: The Synergetic Geometry ofR. Buckminster Fuller, 1987 Marjorie Senechal and Shaping Space: A Polyhedral George Fleck (Eds.) Approach, 1988 Judith Wechsler (Ed.) On Aesthetics in Science, 1988 Lois Swirnoff Dimensional Color, 1989 Arthur L. Loeb Space Structures: Their Harmony and Counterpoint, 1991 Arthur L. Loeb Concepts and Images I, 1992 Arthur L. Loeb Concepts and Images II, in preparation Illustrations ............. ix Foreword by CYRIL STANLEY SMITH xiii Pretext ................ xv Introduction ............. xvii Chapter 1. The Parameters of Structure 1 2. Valencies ......... 5 3. The Eu1er-Sch1aefli Equation 11 4. Statistical Symmetry . . . . 17 5. Random Two-dimensional Nets 23 6. Degrees of Freedom 29 7. Duality . . . . . . 39 8. Schlegel Diagrams 45 9. Regular Structures 51 10. Truncation and Stellation 63 11. Stellation and Truncation 79 12. Exhaustive Enumeration of the Semiregular Two-dimensional Structures ........ 91 13. Dirichlet Domains in a Plane . . . . . . . . III 14. Dirichlet Domains of Regularly Spaced Planar Arrays ............. 117 15. Lattices and Lattice Complexes. . . . . . 123 16. Space-filling Polyhedra . . . . . . . . . . 127 17. Additional Space Fillers and their Lattice Complexes. . . . . . . . . . . . . . . 133 18. Orthorhombic and Tetragonal Lattices . . 139 Coda: Unwrapping the Cube: A Photographic Essay with technical assistance of C. TODD STUART and photography by BRUCE ANDERSON 147 Bibliography 163 Index . . . . . . . . . . . . . . . . . . . . . . . 185 vii page Fig. l-la and 1-1 b Singly (a) and doubly (b) connected surfaces 2 2-1 The number zero 5 2-2 The number 1 5 2-3 The number 2 5 2-4 The number 3 7 2-5 The number 4 7 2-6 A tree graph 8 2-7 Digonal dihedron 9 3-1 Tetrahedron: V = 4, E = 6, F =4 , C = 2 13 3-2 Three-dimensional figure having tetrahedral cells 13 5-1 An irregular two-dimensional structure 24 6-1 Triangular bipyramid 31 6-2 Square pyramid 31 6-3 Top view of pentagonal bipyramid 33 = 6-4 Eight vertices, six 5-fold, two 3-fold, r 4-1/2 34 = 6-5 Eight vertices, four 6-fold, four 3-fold, r 4-1/2 34 6-6 Icosahedron 35 7-1 Cube 41 7-2 Octahedron 41 7-3 Truncated Octahedron 41 7-4 Stellated Cube 41 7-5 Tetrahedron 41 7-6 Truncated Tetrahedron 42 7-7 Stella ted Tetrahedron 42 7-8 eu boctahedron 42 7-9 Rhombohedral Dodecahedron 42 8-1 Schlegel diagram of a cube 46 8-2 Schlegel diagram of an octahedron 46 8-3 Schlegel diagram of a tetrahedron 47 8-4 Triangular bipyramid 47 8-5 Schlegel diagram of a rhombohedral dodecahedron 48 ix x ILLUSTRATIONS 8-6 Dual Schlegel diagram for the octahedron 48 8-7 Dual Schlegel diagram for the cube 49 8-8 Dual Schlegel diagram for the tetrahedron 50 9-1 Digonal dihedron 52 9-2 Digonal trihedron 52 9-3 Trigonal tetrahedron 53 9-4 Cube 53 9-5 Pentagonal dodecahedron 53 9-6 Hexagonal tessellation 53 9-7 Digonal tetrahedron 54 9-8 Octahedron 54 9-9 Quadrilateral tessellation 54 9-10 Icosahedron 55 9-11 Triangular tessellation 56 9-12 Structure having s = 3, r = 4, 1 = 3, m = 2, k = 3, n = 2 57 9-13 Hypertetrahedron 59 9-14 Hypercube 59 9-15 Hyperoctahedron 60 10-1 Edge truncation 64 10-2 Edge stellation 65 10-3 Schlegel diagram of the edge-truncated tetrahedron (equivalent to truncated octahedron) 66 10-4 Schlegel diagram of the edge-truncated octahedron or cube (great rhombicuboctahedron) 66 10-5 Schlegel diagram of the edge-truncated icosahedron or dodecahedron (great rhombicosidodecahedron) 68 10-6 Prism resulting from the edge truncation of a digonal trihedron and of a trigonal dihedron 69 10-7 Edge-truncated triangular or hexagonal tessellation 69 10-8 Edge-truncated square tessellation 69 10-9 Coordinates of a general point complex in the crystallographic cubic lattice 70 10-10 Summary of special truncations 72 10-11 Vertex-truncated n-gonal dihedron 74 10-12 Vertex-truncated tf-angular tessellation (hexagonal tessellation) 74 10-13 Vertex-truncated square tessellation (octagon- square tessellation) 74 10-14 Vertex-truncated hexagonal tessellation (dodecagon- triangle tessellation) 74 10-15 Vertex-truncated tetrahedron 75 10-16 Vertex-truncated octahedron 75 10-17 Vertex-truncated cube 75 10-18 Vertex-truncated pentagonal dodecahedron 75 10-19 Vertex-truncated icosahedron 75 10-20 Degenerate truncation of triangular or hexagonal tessellations 76 ILLUSTRATIONS xi 10-21 Cub octahedron 76 10-22 Icosidodecahedron 76 10-23 Degenerate truncation of a polygonal dihedron or digonal polyhedron 76 11-1 Special stellations 80 11-2 Edge-stellated tetrahedron 81 11-3 Edge-stellated octahedron or cube 81 11-4 Edge-stellated icosahedron or pentagonal dodecahedron 83 11-5 Edge-stellated triangular or hexagonal tessellation 83 11-6 Edge-stellated quadrilateral tessellation 84 11-7 Bipyramid 84 11-8 Face-stellated (triakis) tetrahedron 84 11-9 Face-stellated (triakis) octahedron 84 11-10 Face-stellated cube (tetrakis Hexahedron) 84 II-II F ace-stellated icosahedron (triakis icosahedron or hexecontahedron) 86 11-12 Face-stellated pentagonal dodecahedron (pentakis dodecahedron) 86 11-13 Face-stellated triangular tessellation 86 11-14 Face-stellated square tessellation 86 11-15 Face-stellated digonal polyhedron 86 11-16 Rhombohedral triacontahedron 87 11-17 Degenerately stella ted digonal polyhedron or polygonal dihedron 89 11-18 Degenerately stella ted triangular or hexagonal tessella tions 89 12-1 , = 3, n = 6 92 12-2 Structure having triangular faces and two possible vertex valencies 95 12-3 Icositetrahedron 97 12-4 Dual Schlegel diagrams of two icositetrahedral forms 98 12-5 Trapezohedron projection 98 12-6 Two tessellations having n 1 = 3, n2 = 2,'1 = 3,'2 = 4 99 12-7 Tessellation having n 1 = 4, n2 = 1,' 1 = 3,'2 = 6 100 12-8 Pen tagonal icositetrahedron 100 12-9 Pentagonal hexecontahedron 100 12-10 Three mutually equivalent faces joined at a trivalent vertex 103 12-11 Trapezoidal hexecontahedron 104 12-12 Tessellation resulting from the superposition of a triangular and hexagonal net 104 12.-13 Pentagonal antiprism 106 12-14a Dual of icositetrahedral structure 106 (a) Small rhombicuboctahedron 12-14b Dual of icositetrahedral structure 106 (b) Twist small rhombicuboctahedron