o these
investigations with the ultimate purpose of solving the difficult
problem of Aeronautics. To this he devotes the last fifty pages of his
book. Dr. Pettigrew is confident that man will yet conquer the domain
of the air."--_N. Y. Journal of Commerce._

"Most persons claim to know how to walk, but few could explain the
mechanical principles involved in this most ordinary transaction, and
will be surprised that the movements of bipeds and quadrupeds, the
darting and rushing motion of fish, and the erratic flight of the
denizens of the air, are not only analogous, but can be reduced to
similar formula. The work is profusely illustrated, and, without
reference to the theory it is designed to expound, will be regarded as
a valuable addition to natural history."--_Omaha Republic._

IX.

Responsibility in Mental Disease.

By HENRY MAUDSLEY, M.D.,

Fellow of the Royal College of Physicians; Professor of Medical
Jurisprudence in University College, London.

1 vol., 12mo. Cloth. Price, $1.50.

"Having lectured in a medical college on Mental Disease, this book has
been a feast to us. It handles a great subject in a masterly manner,
and, in our judgment, the positions taken by the author are correct
and well sustained."--_Pastor and People._

"The author is at home in his subject, and presents his views in an
almost singularly clear and satisfactory manner.... The volume is a
valuable contribution to one of the most difficult, and at the same
time one of the most important subjects of investigation at the
present day."--_N. Y. Observer._

"It is a work profound and searching, and abounds in wisdom."--_Pittsburg
Commercial._

"Handles the important topic with masterly power, and its suggestions
are practical and of great value."--_Providence Press._

X.

The Science of Law.

By SHELDON AMOS, M.A.,

Professor of Jurisprudence in University College, London; author of "A
Systematic View of the Science of Jurisprudence," "An English Code,
its Difficulties and the Modes of overcoming them," etc., etc.

1 vol., 12mo. Cloth. Price, $1.75.

"The valuable series of 'International Scientific' works, prepared by
eminent specialists, with the intention of popularizing information in
their several branches of knowledge, has received a good accession in
this compact and thoughtful volume. It is a difficult task to give the
outlines of a complet