9. For the embodiment of all recent discoveries in the various departments of philosophy. Instead of relying on the obsolete authorities that have furnished the matter for many of our popular school Philosophies, the author has made it his business to acquaint himself with the present state of science, and thus produced such a work as is demanded by the progressive spirit of the age. All who have examined this book commend it in the highest terms. "Mr. QUACKENBOS has long been favorably known as a teacher and also a writer of educational books. This elementary work on Natural Philosophy strikes us as being one of his most useful and happy efforts."--_N. Y. Courier and Enquirer._ "A very complete system. We have been particularly struck with the conciseness and intelligible character of the definitions and explanations."--_N. Y. Observer._ "It is much the most complete and instructive school-book on Natural Philosophy that we have ever seen."--_Christian Union, Louisville, Ky._ "Every reasonable requirement is met in this new work."--_Gazette, Pittsburg, Pa._ "The whole arrangement is decidedly superior to anything of the kind that ever fell under our inspection."--_Post, Hartford, Conn._ "It places the principles and rules of philosophy within the reach of the young student in a most attractive form."--_Evening Transcript, Boston._ * * * * * THE SERIES COMPLETED * * * * * PERFECTED EDITIONS OF Webster's Dictionaries, FOR SCHOOLS AND EDUCATIONAL INSTITUTIONS OF EVERY GRADE, AS WELL AS FAMILIES AND GENERAL USE. WEBSTER'S POCKET DICTIONARY, Diamond, 32mo. Prices 50 cts. and 84 cts. WEBSTER'S PRIMARY SCHOOL DICTIONARY, 304 pp., 16mo. Price 50 cts. WEBSTER'S COMMON SCHOOL DICTIONARY, 320 pp., 12mo. Price 75 cts. WEBSTER'S HIGH SCHOOL DICTIONARY, 350 pp., 12mo. Price $1 00. WEBSTER'S ACADEMIC DICTIONARY, 472 pp., cap 4to. Price $1 50. WEBSTER'S COUNTING-HOUSE AND FAMILY DICTIONARY, 522 pp., Imperial 12mo. Price $1 75.