Sound: A Course of Eight Lectures

Mr. Fryer adds that his Chinese friend had no difficulty in grasping every idea in the book.

The most significant new material introduced into this edition is an account of an investigation that I have had the honor of conducting over the past two years in collaboration with the Elder Brethren of Trinity House Trinity House is the official authority for lighthouses in England and Wales; the "Elder Brethren" are its senior historical board members.. Under the title "Researches on the Acoustic Transparency of the Atmosphere, in relation to the question of Fog-signaling," this subject is treated in Chapter VII of this volume.

This investigation could only have been carried out using government resources and equipment. I am pleased to believe that not only have the practical goals of the inquiry been achieved, but also that a multitude of scientific errors, which have surrounded this subject for more than a century and a half, have been removed. These errors have now been replaced by the certain truths of nature. In writing the account of this laborious inquiry, I aimed to connect the observations so closely that they alone would provide a substantial demonstration of the principles involved. Further work allowed me to subject the entire inquiry to rigorous experimentation, thereby giving it a level of certainty that it could hardly have enjoyed without this final guarantee.

Immediately after the first brief summary of the investigation was published, it faced criticism. I did not feel it necessary to respond to this, believing that the reasons for the criticism would vanish once the full account was available. The only opinion I felt it right to consider was a somewhat private one, shared with me by Professor Stokes Sir George Gabriel Stokes (1819–1903) was a physicist and Lucasian Professor of Mathematics at Cambridge, famous for his work on fluid dynamics and optics.. He believed that I had, in some cases, attributed too exclusive an influence...