The term "dislocation" is used in several different senses in the literature of mechanics. In the elassic work of VOLTERRA, WEINGARTEN, and SOMIGLIANA, it refers to particular solutions of the equations of linear elasticity, in which a con tinuous field of strain does not correspond, globally, to a continuous field of dis placement. The configuration of the body so obtained, even when that body is free of all load, is subject to interior stress that does not vanish, and in general no deformation of the body as a wh oIe can bring it into a stress-free configuration. Nevertheless, if any sufficiently sm all part of the body is considered by itself, a configuration for it in which the stress is everywhere zero may be found at once. In this work constitutiL"e assumptions provide the basic data. These consist in prescribed stress-free configurations for each material point and in prescribed elastic moduli governing the response to deformation from the stress-free configuration at each material point. Everything follows from these data, ineluding the dislocations present, if any. In particular, the common boundary-value problems of linear elasticity may be set and solved for the dislocated body.

This book presents a recasting of Aristotle’s theory of spatial displacement of inanimate objects. Aristotle’s claim that projectiles are actively carried by the media through which they move (such as air or water) is well known and has drawn the attention of commentators from ancient to modern times. What is lacking, however, is a systematic investigation of the consequences of his suggestion that the medium always acts as the direct instrument of locomotion, be it natural or forced, while original movers (e.g. stone throwers, catapults, bowstrings) act indirectly by impressing moving force into the medium. Filling this gap and guided by discussions in Aristotle’s Physics and On the Heavens, the present volume shows that Aristotle’s active medium enables his theory - in which force is proportional to speed - to account for a large class of phenomena that Newtonian dynamics - in which force is proportional to acceleration - accounts for through the concept of inertia. By applying Aristotle’s medium dynamics to projectile flight and to collisions that involve reversal of motion, the book provides detailed examples of the efficacy and coherence that the active medium gives to Aristotle’s discussions. The book is directed primarily to historians of ancient, medieval, and early modern science, to philosophers of science and to students of Aristotle’s natural philosophy.

In the long history of philosophy and literature, few have been so widely read and admired as the great thinkers of Greece and Rome. For modern audiences, this eBook bundle—which collects the Modern Library editions of three classics: Marcus Aurelius’ Meditations, Selected Dialogues of Plato, and The Basic Works of Aristotle—is the perfect introduction to the foundation of modern knowledge. Accompanied by insightful, accessible commentary from some of today’s top scholars, including Gregory Hays, Hayden Pelliccia, and C.D.C. Reeve, this is a collection of ideas that changed the world—and have truly stood the test of time. MEDITATIONS Marcus Aurelius succeeded his adoptive father as emperor of Rome in A.D. 161—and Meditations remains one of the greatest works of spiritual and ethical reflection ever written. The Meditations have become required reading for statesmen and philosophers alike, while generations of readers have responded to the straightforward intimacy of the leader’s style. In Gregory Hays’s seminal translation, Marcus’s thoughts speak with a new immediacy: Never before have they been so directly and powerfully presented. SELECTED DIALOGUES OF PLATO In this volume, Hayden Pelliccia has revised five of Benjamin Jowett’s translations of Plato—classics in their own right—to produce a fresh, modern take that Library Journal calls “a needed and welcome addition to the translations of the Dialogues.” Here are Ion, Protagoras, Phaedrus, and the famous Symposium, which discuss poetry, the Socratic method, rhetoric, psychology, and love. Most dramatically, Apology puts Socrates’ art of persuasion to the ultimate test—defending his own life. THE BASIC WORKS OF ARISTOTLE Preserved by Arabic mathematicians and canonized by Christian scholars, Aristotle’s works have shaped Western thought, science, and religion for nearly two thousand years—and Richard McKeon’s edition has long been considered the best available one-volume Aristotle. Here are selections from the Organon, On the Heavens, The Short Physical Treatises, Rhetoric, among others, and On the Soul, On Generation and Corruption, Physics, Metaphysics, Nicomachean Ethics, Politics, and Poetics in their entirety.