/0/16526/coverbig.jpg?v=41539f073b92b0939fe6d8bb58a1bd45&imageMogr2/format/webp)
Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.
Chapter 1 * * *
Prefatory Note
M. Lucien Poincaré is one of the distinguished family of mathematicians which has during the last few years given a Minister of Finance to the Republic and a President to the Académie des Sciences. He is also one of the nineteen Inspectors-General of Public Instruction who are charged with the duty of visiting the different universities and lycées in France and of reporting upon the state of the studies there pursued. Hence he is in an excellent position to appreciate at its proper value the extraordinary change which has lately revolutionized physical science, while his official position has kept him aloof from the controversies aroused by the discovery of radium and by recent speculations on the constitution of matter.
M. Poincaré's object and method in writing the book are sufficiently explained in the preface which follows; but it may be remarked that the best of methods has its defects, and the excessive condensation which has alone made it possible to include the last decade's discoveries in physical science within a compass of some 300 pages has, perhaps, made the facts here noted assimilable with difficulty by the untrained reader. To remedy this as far as possible, I have prefixed to the present translation a table of contents so extended as to form a fairly complete digest of the book, while full indexes of authors and subjects have also been added. The few notes necessary either for better elucidation of the terms employed, or for giving account of discoveries made while these pages were passing through the press, may be distinguished from the author's own by the signature "ED."
THE EDITOR.
ROYAL INSTITUTION OF GREAT BRITAIN, April 1907.
* * *
Author's Preface
During the last ten years so many works have accumulated in the domain of Physics, and so many new theories have been propounded, that those who follow with interest the progress of science, and even some professed scholars, absorbed as they are in their own special studies, find themselves at sea in a confusion more apparent than real.
It has therefore occurred to me that it might be useful to write a book which, while avoiding too great insistence on purely technical details, should try to make known the general results at which physicists have lately arrived, and to indicate the direction and import which should be ascribed to those speculations on the constitution of matter, and the discussions on the nature of first principles, to which it has become, so to speak, the fashion of the present day to devote oneself.
I have endeavoured throughout to rely only on the experiments in which we can place the most confidence, and, above all, to show how the ideas prevailing at the present day have been formed, by tracing their evolution, and rapidly examining the successive transformations which have brought them to their present condition.
In order to understand the text, the reader will have no need to consult any treatise on physics, for I have throughout given the necessary definitions and set forth the fundamental facts. Moreover, while strictly employing exact expressions, I have avoided the use of mathematical language. Algebra is an admirable tongue, but there are many occasions where it can only be used with much discretion.
Nothing would be easier than to point out many great omissions from this little volume; but some, at all events, are not involuntary.
Certain questions which are still too confused have been put on one side, as have a few others which form an important collection for a special study to be possibly made later. Thus, as regards electrical phenomena, the relations between electricity and optics, as also the theories of ionization, the electronic hypothesis, etc., have been treated at some length; but it has not been thought necessary to dilate upon the modes of production and utilization of the current, upon the phenomena of magnetism, or upon all the applications which belong to the domain of Electrotechnics.
/0/95388/coverorgin.jpg?v=420b7905e933001a5a67682ee14c22f7&imageMogr2/format/webp)
/0/86395/coverorgin.jpg?v=55bb4b33b13d15db79b49aea662af755&imageMogr2/format/webp)
/0/92811/coverorgin.jpg?v=e6a58467c814dabe499538a9b77737c3&imageMogr2/format/webp)
/0/93964/coverorgin.jpg?v=5c32ee5a5ac33a7f88c747f1d102b76f&imageMogr2/format/webp)
/0/85173/coverorgin.jpg?v=95f4c350fdd6a7bee4bd59ff686ca121&imageMogr2/format/webp)
/1/100111/coverorgin.jpg?v=e850e95497c801aebc8533c91eee1448&imageMogr2/format/webp)
Chapter 1 * * *
06/12/2017
Chapter 2 THE EVOLUTION OF PHYSICS
06/12/2017
Chapter 3 MEASUREMENTS
06/12/2017
Chapter 4 PRINCIPLES
06/12/2017
Chapter 5 THE VARIOUS STATES OF MATTER
06/12/2017
Chapter 6 SOLUTIONS AND ELECTROLYTIC DISSOCIATION
06/12/2017
Chapter 7 THE ETHER
06/12/2017
Chapter 8 A CHAPTER IN THE HISTORY OF SCIENCE
06/12/2017
Chapter 9 THE CONDUCTIVITY OF GASES AND THE IONS
06/12/2017
Chapter 10 CATHODE RAYS AND RADIOACTIVE BODIES
06/12/2017
Chapter 11 THE ETHER AND MATTER
06/12/2017
Chapter 12 THE FUTURE OF PHYSICS
06/12/2017