xii INTRODUCTION 



is afforded by the development of wireless telegraphy. The 

 now familiar electric waves, transmitted by the ether with the 

 velocity of light, were foreshadowed by Faraday and Henry 

 and definitely made known by the mathematical investigations 

 of Maxwell about the middle of the nineteenth century. 

 Nearly forty years later Hertz, deliberately following Max- 

 well's lead, produced and detected these waves experimentally. 

 Crookes foresaw their possible utilization for wireless teleg- 

 raphy, which was accomplished over short distances by Lodge 

 in 1894, and applied on a commercial scale by Marconi in 1896. 

 The wireless telephone was a later development of the 

 pioneer work of Maxwell and Hertz, reenforced by much ad- 

 ditional physical research on electric discharges in vacuum 

 tubes and other laboratory phenomena. Similarly the inven- 

 tion of the telephone goes back to the principles of magnetic- 

 electric induction discovered by Faraday; the anti-toxin treat- 

 ment of disease grew out of Pasteur's investigations of bac- 

 teria, which resulted in their turn from his studies of the na- 

 ture of certain crystals, made for the sole purpose of advancing 

 knowledge; the airplane had its origin in Langley's researches 

 on the resistance of the air to moving bodies. Analyze any in- 

 vention, and it will be found that it was rendered possible by 

 the work of men concerned only with the advancement of sci- 

 ence. How clearly this is appreciated by the chief leaders 

 of industry is best expressed in the words of Carty, from his 

 presidential address to the American Institute of Electrical 

 Engineers in 1916. 



" It was Michael Faraday, one of the greatest of the workers 

 in pure science, who in the last century discovered the principle 

 of the dynamo electric machine. Without a knowledge of this 

 principle discovered by Faraday the whole art of electrical en- 

 gineering as we know it today could not exist and civilization 

 would have been deprived of those inestimable benefits which have 

 resulted from the work of the members of this Institute. 



" Not only Faraday in England, but Joseph Henry in our own 

 country and scores of other workers in pure science have laid the 



