We have printed a thousand copies of a handsome book of eighty-four pages, entitled "Some Wonders of Science." Besides a number of splendid full-page photogravures and half-tone illustrations, it contains four articles you will want to read. They are: "Liquid Air," by Ray Stannard Baker; "The Man-Like Apes," by Thomas H. Huxley; "Mars, the Miniature of Our Earth,' by Richard A. Proctor; and "History of the Art of Writing," by Edward B. Tylor. Virile, clear, and terse, these articles are intensely interesting from beginning to end. We will send this book free in order to interest you in our new sixteen-volume work.

The New Science Library

which contains just what you would like to know about modern science. You will find in its volumes the best work of Darwin, Huxley, Spencer, Tyndall; together with that of many other scientists who have contributed to the amazing progress of the last fifty years. It is an autobiograpy of the wonderful nineteenth century, written by the men who have played prominent parts. It covers comprehensively the entire field of Science,-Astronomy, Geology, Invention, Discovery, Natural Philosophy, Anthropology, Evolution, Political Economy and Electricity. The Fairy Land of Science

The New Science Library will introduce you to a land of wonders far more marvelous than Hans Christian Andersen's. It will show you marvels of earth, sea and sky, of man and bird and beast. It will tell you how prehistoric man lived and fought tens of thousands of years ago; how electricity sends the trolley car speeding through our cities; it will tell you what secrets the thousand-year-old stones yield to the geologist. We want to prove to you that you will find Science not only instructive but enjoyable, and therefore we want to send you a copy of "Some Wonders of Science.' There are only a thousand copies; mail the coupon at the top of this advertisement to-day and get one of them.

PUBLIC OPINION COMPANY 44-60 East 23d Street NEW YORK