TRANSLATORS' NOTE
HERTZ'S Miscellaneous Papers form the first volume of his
collected works, as edited by Dr. Philipp Lenard. The second
volume is a reprint of his Researches on the Propagation of
Electric Action (already published in English under the title
of Electric Waves). The third volume consists of his Principles
of Mechanics, of which an English translation is now in the
press.
Professor Lenard has shown a warm interest in the
translation, and we desire to express our hearty thanks to
him for his kind assistance.
The portrait which forms the frontispiece to this volume
has been specially engraved for it from a photograph by R.
Krewaldt of Bonn.
March 1896.
D. E. J.
G. A. S.