Introduction

SINCE 1905, when Prof. A. Einstein published his Principle of Relativity in its special form, much attention has been devoted to the subject in scientific circles, and during the last two or three years keen interest has been shown in it by many general readers of intellectual type. Nearly a thousand books, pamphlets, and papers have appeared in which the principle as a whole is described, or some of its aspects are discussed, and among these are a few which aim at making its character and consequences clear without the mathematical expressions which give it precise significance. A praiseworthy essay of this kind is that by Mr. L. Bolton, a senior examiner in the Patent Office, published in the Westminster Gazette on Monday by arrangement with the Scientific American, which awarded it a prize of five thousand dollars as the clearest explanation of Einstein's principle for general readers.