ous musical instruments.

As the speaking-telephone, in which magneto-electric currents were
utilized for the transmission of speech and other kinds of sounds, was
invented by me, I have described at some length my first instrument, and
have also given explicit directions for making a speaking-telephone
which I know, by trial, to be as efficient as any hitherto made; but
nothing in the book is to be taken as a dedication of the invention to
the public, as steps have already been taken to secure letters-patent
according to the laws of the United States.

A. E. DOLBEAR.

COLLEGE HILL, MASS.

THE TELEPHONE.

ELECTRICITY.

SOME of the phenomena of electricity are manifested upon so large a
scale as to be thrust upon the attention of everybody. Thus lightning,
which accompanies so many showers in warm weather in almost every
latitude, has always excited in some individuals a superstitious awe, as
being an exhibition of supernatural agency; and probably every one feels
more or less dread of it during a thunder-shower, and this for the
reason that it affects so many of the senses at the same time. The flash
may be blinding to the eyes if near to us; the thunder may be deafening
to the ears, and so powerful as to shake the foundations of the hills,
and make the ground upon which we stand to sensibly move: these with the
remembered destructive effects that have been witnessed, of buildings
demolished and large trees torn to splinters in an instant, are quite
sufficient to raise a feeling of dread in the strongest mind. In the
polar regions, both north and south, where thunder-storms are less
frequent, the atmospheric electricity assumes the form called the aurora
borealis, or the aurora australis, according as it is seen north or
south of the equator.

More than two thousand years ago it was noticed by the Greeks that a
certain kind of a mineral which was thrown up on the shores of the
Mediterranean Sea, when rubbed would attract light bodies, such as
shreds of silk or linen and bits of paper. To this substance they gave
the name of Elektron, and the property developed thus by friction was
afterwards called electricity. In 1600 Dr. Gilbert, physician to Queen
Elizabeth, published a book in which he described numerous experiments
demonstrating that electricity could be developed by friction upon a
great variety of substances, such as stones, gems, and resins.