A Catechism of Familiar Things; / Their History, and the Events Which Led to Their Discovery. / With a Short Explanation of Some of the Principal Natural Phenomena. For the Use of Schools and Families. Enlarged and Revised Edition.

THE AURORA BOREALIS IN THE ARCTIC REGIONS.
This book, a reprint of a successful English publication, has been so enlarged as to be to all intents and purposes new. It has been carefully revised by a Reverend gentleman, who for some time filled the chair of Physics and Chemistry in one of our colleges.
Recent inventions and improvements are described in a simple, popular style, so as to be easily understood by all, and short notices are given of prominent inventors and scientists. The paragraphs relating to doctrinal matters conform in every respect to the teachings of the Church.
A feature which will commend the book to every teacher is the definitions of difficult words and terms, following the paragraphs in which such words occur.
Technical language is avoided as much as possible, so as to enable young pupils to become familiarly acquainted with the various phenomena of nature, the leading characteristics and general history of the objects of the animal, vegetable, and mineral kingdoms, and the fundamental truths of the arts and sciences.
The illustrations are of a superior order, and a very complete Index, which will be appreciated by every teacher, supplements the book. In a word, no pains have been spared to enhance the value of the work, and render it an important auxiliary in the dissemination of useful and entertaining knowledge.
The publishers beg to acknowledge their obligations to the Sisters of Mercy, Loretto, Pa., to whose kindness they are indebted for many valuable suggestions.
In the hope that the book may be found suited to the accomplishment of its aim, it is respectfully submitted to schools and instructors of youth, who are the best judges of its merits.

What is Dew?
Moisture collected from the atmosphere by the action of cold. During the day, the powerful heat of the sun causes to arise from the earth and water a moist vapor, which, after the sun sinks below the horizon, is condensed by the cold, and falls in the form of dew. Dews are more copious in the Spring and Autumn than at any other season; in warm countries than in cold ones: because of the sudden changes of temperature. Egypt abounds in dews all the summer; for the air being too hot to condense the vapors in the day-time, they never gather into clouds and form rain.