ON SCIENCE AND ART: Ꭱ Ꭲ ; DELIVERED IN THE PRINCIPAL CITIES AND TOWNS OF THE UNITED STATES. BY DIONYSIUS LARDNER, DOCTOR OF CIVIL LAW, FELLOW OF THE ROYAL SOCIETIES OF LONDON AND EDINBURGH- FOR THE ADVANCEMENT OF SCIENCE, AND FORMERLY PROFESSOR OF ASTRON- "The most obvious means of elevating the people, is to provide for them works on popular and prac- IN TWO VOLUMES. VOL. L FIFTEENTH EDITION. - NEW YORK: HENRY W. LAW, PUBLISHER, 310 BROADWAY. 1856. K F3 971 in the Clerk's Office of the District Court of the United States, in and for the Southern District of New York. HARVARD Entered, according to Act of Congress, in the year 1845, BY GREELEY & MCELRATH, PUBLISHERS' ADVERTISEMENT. THE publishers announce that Dr. LARDNER, having brought to a close his public lectures in this country, they have availed themselves of the opportunity thus presented to induce him to prepare for publication the present complete and authentic edition of these discourses. The general interest which they excited in every part of this country is universally felt and acknowledged. Probably no public lecturer ever continued for the same length of time to collect around him so numerous audiences. Nor has there been any exception to this favorable impression. Visit after visit has been made to all the chief cities; and, on every succeeding occasion, audiences amounting to thousands have assembled to hear again and again these lessons of useful knowledge. The same simplicity of language, perspicuity of reasoning, and felicity of illustration, which rendered the oral discourses so universally acceptable, are preserved in these miscellanies, which are, as nearly as possible, identical with the lectures as they were delivered. The publishers feel that in these volumes they present to the American public a most agreeable offering, and an interesting and useful miscellany of general information, which will also afford that large class of persons, who have attended the lectures, an agreeable means of reviving the impressions from which they have already derived so much profit and pleasure. NEW YORK, April, 1855. THE PUBLISHERS. "In primis, hominis est propria vERI inquisitio atque investigatio. Itaque cum sumum negotiis necessariis, curis que vacui, tum avemus aliquid videre, audire, ac dicere, cognitionemque rerum, aut ocult arum aut admirabilium, ad benè beatéque vivendum necessariam ducimus; ex quo intelligitur, quod VERUM, simplex, sincerumque sit, id esse naturæ hominis aptissimum. Huic veri videndi cupiditati adjuncta est appetitio quædam principatûs, ut remini parere animus benè a naturà informatus velit, nisi præcipienti, aut docenti, aut utilitatis causà justè et legitimè imperanti: ex quo animi magnitudo existit, et humanarum rerum contemtio."-Cicero, de Officiis, lib. 1, § 13. Above all things, man is distinguished by his pursuit and investigation of TRUTH, and hence, when free from needful business and cares, we delight to see, to hear, and to communicate, and consider a knowledge of many admirable and abstruse things necessary to the good conduct and happiness of our lives. Whence it is clear, that whatsoever is TRUE, simple, and direct, the same is most congenial to our nature as men. Closely allied with this earnest longing to see and know the truth, is a kind of dignified and princely sentiment which forbids a mind, naturally well constituted, to submit its faculties to any but those who announce its precept and doctrine, or to yield obedience to any orders but sich as are at once just. lawful, and founded on utility From this source spring greatness of mind and conterapt of worldly advantages and troubles PREFACE. IN presenting to the American public the collection of scientific miscellanies which forms the contents of these volumes, it may be proper to explain the circumstances which gave occasion to them in their original form of oral discourses, the character of the audiences to which they were addressed, and of the readers to whose information and amusement it is hoped they may contribute in their present more permanent state. Engaged for a large portion of my life in the practical application of the physical sciences to the uses of life, and more especially to those scientific industries which derive their efficacy from the agency of steam, I had always looked forward with the liveliest interest to a time when I might be enabled to visit a country which had taken so prominent a part in the advancement of these arts, and which had formed from an early period so grand a theatre for their development, as the United States. To the claims which that country presented to the attention of every intelligent and inquiring tourist, arising from its important commercial relations with the old |