Curiosities of Light and Sound

by Shelford Bidwell

Overview

Everyone who has learnt the manipulation of light and of lenses by the practical use of a magic lantern or by photography which involves a little more than the pressing of buttons and the sending of films to be developed, knows enough to follow Mr. Bidwell's lectures on light and sight. Mr. Bidwell is an authority on his subject, but he has the special faculty of explaining technical matters in simple language, and he has devised a series of experiments which can be repeated or modified easily. After a general chapter on the nature of light, he shows the relation of the eye to radiations, and makes extremely plain the troublesome subjects of complementary colors, chromatic dispersion, astigmatism and so forth. Light, treated in this experimental fashion, forms an admirable introduction to science. There is a wide field for cultivating the powers of observation and for the faculties by which observations are combined and analyzed. In the interpretation of the knowledge gained in this way, the fundamental problem of science or of philosophy is raised in a direct fashion; the problem as to how far our perceptions correspond with what may be called objective facts, and how far they are merely functions of our perceiving apparatus.

-The Saturday Review, Vol. 90 [1901]

Product Details

ISBN-13:	9781663516213
Publisher:	Dapper Moose Entertainment
Publication date:	06/11/2020
Pages:	236
Product dimensions:	6.00(w) x 9.00(h) x 0.54(d)

About the Author

Shelford Bidwell FRS (6 March 1848 – 18 December 1909) was an English physicist and inventor. He is best known for his work with "telephotography", a precursor to the modern fax machine. In the late 1870s, he carried out a number of experiments with selenium photocells. In one experiment, he duplicated the "photophone" originally created by Alexander Graham Bell. This device used sound to vibrate a mirror. Variations in light intensity reflected from the vibrating mirror were detected using a selenium photocell which was then connected to a telephone. This showed that voice communication could be transmitted using light beams with a photocell used to convert it to an electrical signal. In the June 4, 1908 issue of Nature, article "Telegraphic Photography and Electric Vision", Bidwell reported on "telegraphic photography" experiments by other scientists and commented on the greater difficulties faced by those wishing to develop "distant electric vision".