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SOUND:

_A Series of Simple, Entertaining, and Inexpensive Experiments in the
Phenomena of Sound, for the Use of Students of Every Age._

By ALFRED MARSHALL MAYER,

Professor of Physics in the Stevens Institute of Technology; Member of
the National Academy of Sciences, etc.

Uniform with "LIGHT," first volume of the Series.

Neat 12mo volume, fully illustrated. Cloth, price, $1.00.

"It would be difficult to find a better example of a series which is
excellent throughout. This little work is accurate in detail, popular
in style, and lucid in arrangement. Every statement is accompanied
with ample illustrations. We can heartily recommend it, either as an
introduction to the subject or as a satisfactory manual for those who
have no time for perusing a larger work. It contains an excellent
description, with diagrams, of Faber's Talking Machine and of Edison's
Talking Phonograph, which can not fail to be interesting to any reader
who takes an interest in the marvelous progress of natural
science."--_British Quarterly._

"The style of the book is very clear, and the experiments interesting.
It can not fail to have an important educational influence."--_Westminster
Review._

"It would really be difficult to exaggerate the merit, in the sense of
consummate adaptation to its modest end, of this little treatise on
'Sound.' It teaches the youthful student how to make experiments for
himself, without the help of a trained operator, and at very little
expense. These hand-books of Professor Mayer should be in the hands of
every teacher of the young."--_New York Sun._

"An admirably clear and interesting collection of experiments,
described with just the right amount of abstract information and no
more, and placed in progressive order. The recent inventions of the
phonograph and microphone lend an extraordinary interest to this whole
field of experiment, which makes Professor Mayer's manual especially
opportune."--_Boston Courier._

* * * * *

The Works of Professor E. L. YOUMANS, M. D.

_Class-book of Chemistry._

New edition. 12mo. Cloth, $1.50.

_The Hand-book of Household Science._

A Popular Account of Heat, Light, Air, Aliment, and Cleansing, in
their Scientific Principles and Domestic Applications. 12mo.
Illustrated. Cloth, $1.75.

_The Culture demanded by Modern Life._

A Series of Addresses and Arguments on the Claims