rial illustrations, make it a most
attractive volume for young persons, while the fullness and accuracy of
the information with which it overflows commends it to the attention of
mature readers. --_N. Y. Tribune._

Like the previous volume, it is in all respects admirable. It is a
mystery to us how Mr. Abbott can so simplify the most abstruse and
difficult principles, in which optics especially abounds, as to bring
them within the grasp of quite youthful readers; we can only be very
grateful to him for the result. This book is up to our latest knowledge
of the wonderful force of which it treats, and yet weaves all its
astounding facts into pleasing and readable narrative form. There are
few grown people, indeed, whose knowledge will not be vastly increased
by a perusal of this capital book. --_N. Y. Evening Mail._

Perhaps there is no American author to whom our young people are under
so great a debt of gratitude as to this writer. The book before us, like
all its predecessors from the same pen, is lucid, simple, amusing, and
instructive. It is well gotten up and finely illustrated, and should
have a place in the library of every family where there are children.
--_N. Y. Star._

It is the second volume of a delightful series started by Mr. Abbott
under the title or "Science for the Young," in which is detailed
interesting conversations and experiments, narratives of travel, and
adventures by the young in pursuit of knowledge. The science of optics
is here so plainly and so untechnically unfolded that many of its most
mysterious phenomena are rendered intelligible at once. --_Cleveland
Plain Dealer._

It is complete, and intensely interesting. Such a series must be of
great usefulness. It should be in every family library. The volume
before us is thorough, and succeeds in popularizing the branch of
science and natural history treated, and, we may add, there is nothing
more varied in its phenomena or important in its effects than light.
--_Chicago Evening Journal._

Any person, young or old, who wishes to inform himself in a pleasant way
about the spectroscope, magic-lantern cameras, and other optical
instruments, and about solar, electric, calcium, magnesium, and all
other kinds of light, will find this book of Mr. Abbott both interesting
and instructive. --_Lutheran Observer._

Published by HARPER & BROTHERS, New York.

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