Transcriber’s Notes: Underscores “_” before and after a word or phrase indicate _italics_ in the original text. Equal signs “=” before and after a word or phrase indicate =bold= in the original text. Small capitals have been converted to SOLID capitals. Illustrations have been moved so they do not break up paragraphs. Typographical and punctuation errors have been silently corrected. SIGNALLING ACROSS SPACE WITHOUT WIRES. BEING A DESCRIPTION OF THE WORK OF HERTZ & HIS SUCCESSORS. BY PROF. OLIVER J. LODGE, F.R.S. THIRD EDITION, _With Additional Remarks concerning the Application_ _to Telegraphy, and Later Developments_. LONDON: “THE ELECTRICIAN” PRINTING AND PUBLISHING COMPANY, LIMITED, SALISBURY COURT, FLEET STREET. _Copyright._ WORKS BY DR. O. J. LODGE. =Lightning Conductors and Lightning Guards.= _A Complete Treatise on the subject of Electric Discharges in general._ =Pioneers of Science.= _A popular Illustrated History of the Early Astronomers and their Work up to Recent Times._ =Modern Views of Electricity.= =Elementary Mechanics.= =Protection of Buildings from Lightning.= _Mann Lectures to the Society of Arts, 1888._ =Secondary Batteries and the Electrical Storage of Energy.= _Cantor Lectures to the Society of Arts, 1883._ TABLE OF CONTENTS. (_The lines in italics which look like headings of paragraphs are really statements about experiments which were at that place shown._)