In conclusion, some of the instruments denominated Screw Propellers are duly noticed, with authentic statements of the results of various experiments in which they were applied, and remarks on those generally in use in Europe and in the United States of America. It will be obvious that the facts thus detailed were widely scattered, and in some few instances difficult of access: they have consequently been collected and arranged from many sources, and the compilation is now submitted as forming a book of reference which may be found not only useful, but interesting to those who seek for information as to the origin and progress of Steam Navigation.—_Preface._ LONDON: TAYLOR, WALTON, AND MABERLY, IVY LANE, PATERNOSTER ROW. 1848. TRANSCRIBER’S NOTE Illustrations in this eBook have been positioned between paragraphs. The index was not checked for proper alphabetization or correct page references. Obvious typographical errors and punctuation errors have been corrected after careful comparison with other occurrences within the text and consultation of external sources. Some hyphens in words have been silently removed, some added, when a predominant preference was found in the original book. Except for those changes noted below, all misspellings in the text, and inconsistent or archaic usage, have been retained. Pg xix: ‘which’ replaced by ‘the’ to match the title of the section. 117: ‘Spunge’ replaced by ‘Sponge’.