Excerpt from The Glasgow Medical Journal, Vol. 89: January to June, 1918 The advent of the electron theory has given us the means of building up a very reasonable explanation of the physical aspect of colour. Although we are not concerned at present with the constitution of matter, it will be of assistance to picture what an atom of matter is now supposed to be. We picture the atom as being composed of nothing but positive and negative electricities. We imagine a core of positive electricity (whatever that may be), and embedded in it a number of particles of negative electricity, each particle of which is called an electron. Around this central core we picture a ring of satellite electrons, revolving at an enormous speed, approaching the velocity of light. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.