Jian-Liang Lin · Hong-Sen Yan Decoding the Mechanisms of Antikythera Astronomical Device Decoding the Mechanisms of Antikythera Astronomical Device Jian-Liang Lin · Hong-Sen Yan Decoding the Mechanisms of Antikythera Astronomical Device 1 3 Jian-Liang Lin Hong-Sen Yan Department of Mechanical Department of Mechanical Engineering Engineering National Cheng Kung University National Cheng Kung University Tainan Tainan Taiwan Taiwan ISBN 978-3-662-48445-6 ISBN 978-3-662-48447-0 (eBook) DOI 10.1007/978-3-662-48447-0 Library of Congress Control Number: 2015950021 Springer Heidelberg New York Dordrecht London © Springer-Verlag Berlin Heidelberg 2016 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made. Printed on acid-free paper Springer-Verlag GmbH Berlin Heidelberg is part of Springer Science+Business Media (www.springer.com) Preface The Antikythera astronomical calculating device invented in the ancient Greece between 150–100 BC was discovered from the Antikythera shipwreck of the Mediterranean in 1900–1901. The device was the oldest astronomical calcula- tor for the function of indicating the date of Egyptian calendar, displaying the motions of the Sun, the Moon, and the five planets, showing moon phases, calcu- lating the calendars, and predicting eclipses. The interior structure of mechanism is composed of gear trains with six subsystems corresponding to its functions. Nevertheless, the device was absolutely strange to everyone in the era of the dis- covery. None of known ancient artifacts bears any resemblance to this excavated mechanical device, and the historical records or literatures about such a geared device were not available. Owing to the damages caused by excavation in some fragments, subsystems are incomplete, unclear, and even lost. Decoding the mech- anisms and reconstructing the device are much more difficult, even with advanced modern image technology. This book presents a unique systematic design methodology to decode the interior mechanisms of the Antikythera device. The historical background, the surviving evidence, and the existing reconstruction works of the device are intro- duced, and the historical development of astronomical achievements and various astronomical instruments is investigated. By utilizing the methodology based on the conceptual design of modern mechanisms, all feasible designs of the six lost/ incomplete/unclear subsystems subject to the standards of science and technology in the time period are synthesized as illustrated examples, and 48 feasible designs of the complete interior mechanisms are presented. Such a design methodology provides not only a logical tool applying the knowledge of mechanical engineer- ing for the reconstruction designs of the Antikythera device, but also an innova- tive research approach for identifying the original structure of mechanisms in the future. The book is organized in such a way that it can be used for research, science edu- cation, and self-study. It can be used as a supplementary note for readers who are interested in the Antikythera device. Chapter 1 outlines the historical development of Western astronomy, including cosmology, calendars, astronomical events, and v vi Preface astronomical theory. Chapter 2 introduces the ancient astronomical instruments and analyzes the designs corresponding to some special functions. Chapter 3 introduces the historical background, known functions, and structure analysis of the Antikythera mechanism. Chapter 4 describes the existing reconstruction works. Chapter 5 pre- sents the design methodology and compares the authors’ reconstruction designs with other available ones. Chapters 6–10 are the reconstruction designs of the calendrical subsystem, the lunar subsystem, the solar subsystem, the planetary subsystem, and the moon phase display device, respectively. Chapter 11 explains the geometric con- straints and detailed designs of assembly work and presents all feasible designs of complete interior structure along with a 3D model. The authors would like to express their gratitude to those who had been of continuous assistance, especially the members of Creative Mechanism Design Research and Education Laboratory in the Department of Mechanical Engineering at National Cheng Kung University (Tainan, Taiwan), as well as the Ministry of Science and Technology (Taipei, Taiwan) for the financial support under Grant NSC 99-2221-E-006-253. The authors believe that this book will meet the needs of academic research, archaeological research, and teaching in the reconstruction designs of ancient machinery and creative designs of modern mechanisms. Comments and sugges- tions for the improvement and revision of the book will be highly appreciated. Tainan, Taiwan Jian-Liang Lin Hong-Sen Yan Contents 1 A Sketch of Ancient Western Astronomy ....................... 1 1.1 Historical Development of Western Astronomy ............... 1 1.1.1 Egyptian Civilization ............................ 2 1.1.2 Mesopotamian Civilization ....................... 4 1.1.3 Aegean Civilization ............................. 5 1.2 Astronomical Cycles and Calendars ....................... 13 1.2.1 Egyptian Calendar .............................. 13 1.2.2 Metonic Cycle ................................. 14 1.2.3 Callippic Cycle ................................ 14 1.2.4 Saros Cycle ................................... 15 1.2.5 Exeligmos Cycle ............................... 15 1.3 Ancient Astronomical Theories ........................... 16 1.3.1 Solar Theory .................................. 16 1.3.2 Lunar Theory .................................. 17 1.3.3 Planetary Theory ............................... 17 1.4 Remarks ............................................. 18 References ................................................. 18 2 Ancient Astronomical Instruments ............................ 21 2.1 Classifications Based on Functions ........................ 21 2.1.1 Observation Application ......................... 22 2.1.2 Measuring Position and Distance Application ........ 22 2.1.3 Measuring Time Application ...................... 23 2.1.4 Computing Application .......................... 24 2.1.5 Demonstration Application ....................... 24 2.2 Jacob’s Staff .......................................... 25 2.3 Astrolabe ............................................ 26 2.4 Sundial .............................................. 28 2.5 Calendrical Device ..................................... 31 2.5.1 Astrolabe with Calendrical Gearing ................ 31 2.5.2 Sundial with Calendrical Gearing .................. 32 vii viii Contents 2.6 Planetarium, Astrarium, and Astronomical Clock ............. 35 2.7 Orrery ............................................... 37 2.8 Comparisons of Astronomical Instruments .................. 38 2.9 Remarks ............................................. 41 References ................................................. 41 3 Amazing Discovery of Archaeology ............................ 45 3.1 Origination and Process of the Discovery ................... 45 3.1.1 Historical Background of Salvage .................. 46 3.1.2 Story of the Antikythera Finding ................... 47 3.2 Introduction of the Excavations ........................... 48 3.3 Known Antikythera Astronomical Device ................... 50 3.3.1 Front Plate .................................... 50 3.3.2 Back Plate .................................... 51 3.3.3 Display Pointers ................................ 53 3.3.4 Interior Structure of Mechanisms .................. 55 3.4 Relative Historical Background and Records ................ 57 3.5 Remarks ............................................. 59 References ................................................. 59 4 Modern Reconstruction Research ............................. 63 4.1 Early Mentions ........................................ 63 4.2 Reconstruction Work by Price ............................ 64 4.3 Reconstruction Work by Edmund and Morgan ............... 67 4.4 Reconstruction Work by Wright ........................... 69 4.5 Reconstruction Work by Freeth et al. ....................... 75 4.6 Others’ Research After AD 2000 .......................... 78 References ................................................. 83 5 Reconstruction Design Methodology ........................... 85 5.1 Reconstruction Research ................................ 85 5.2 Reconstruction Design Methodology ....................... 87 5.2.1 Design Specifications ............................ 89 5.2.2