OF NATURAL PHILOSOPHY; IN WHICH THE PRINCIPLES OF MECHANICS, HYDROSTATICS, HYDRAULICS, PNEUMATICS, ACOUSTICS, OPTICS, ARE FAMILIARLY EXPLAINED, AND ILLUSTRATED BY MORE THAN TWO HUNDRED ENGRAVINGS. TO WHICH ARE ADDED, QUESTIONS FOR THE EXAMINATION OF THE PUPILS DESIGNED FOR THE USE OF SCHOOLS AND ACADEMIES. TWENTY-EIGHTH EDITION. BY J. L. COMSTOCK, M. D. Mem. Con. M. S.; Hon. Mem. R. I. M. S.; Author of Notes to Conv. on Chemistry, New-York: PUBLISHED BY ROBINSON, PRATT, & CO. No. 259 PEARL STREET; D SOLD BY THE PRINCIPAL BOOKSELLERS THROUGHOUT MARYARD COLLEGE LAKY BY EXCHANGE FROM DISTRICT OF CONNECTICUT, ss. BE IT REMEMBERED, That on the twenty-fourth day of May, in the fifty-fifth year of the Independence of the United States of America, J. L. COMSTOCK, of the said District, hath deposited in this office the title of a Book, the right whereof he claims as author and proprietor, in the words following, to wit; "A System of Natural Philosophy; in which the principles of Mechanics, Hydrostatics, Hydraulics, Pneumatics, Acoustics, Optics, Astronomy, Electricity, and Magnetism, are familiarly explained, and illustrated by more than two hundred engravings. To which are added, Questions for the examination of the Pupils. Designed for the use of Schools and Academies. By J. L. Comstock, M. D.; Mem. Con. Med. Soc.; IIon. Mem. R. I. M. S.; Author of Notes to Conv. on Chem.; Author of Gram. Chem.; of Elem. Mineralogy; of Nat. Hist. of Quadr and Birds, &c." In conformity to the act of Congress of the United States, entitled, "an act for the encouragement of learning, by securing the copies of Maps, Charts, and Books, to the authors and proprietors of such copies, during the times therein mentioned."-And also to the act, entitled, "an act supplementary to an act, entitled, 'an act for the encouragement of learning, by securing the copies of Maps, Charts, and Books, to the authors and proprietors of such copies, during the times therein mentioned,' and extending the benefits thereof to the arts of designing, engraving, and etching historical and other prints." CHARLES A. INGERSOLL, Clk. of the Dis. of Connecticut. A true copy of Record, examined and sealed by me, CHARLES A. INGERSOLL, Cik. of V Dis. of Connecticut. PREFACE. WHILE We have recent and improved systems of Geography, of Arithmetic, and of Grammar, in ample variety,--and Reading and Spelling Books in corresponding abundance, many of which show our advancement in the science of education, no one has offered to the public, for the use of our schools, any new or improved system of Natural Philosophy. And yet this is a branch of education very extensively studied at the present time, and probably would be much more so, were some of its parts so explained and illustrated as to make them more easily understood. The author therefore undertook the following work at the suggestion of several eminent teachers, who for years have regretted the want of a book on this subject, more familiar in its explanations, and more ample in its details, than any now in common use. The Conversations on Natural Philosophy, a foreign work now extensively used in schools, though beautifully written, and often highly interesting, is, on the whole, considered by most instructors as exceedingly deficient—particularly in wanting such a method in its explanations, as to convey to the mind of the pupil precise and definite ideas; and also in the omission of many subjects, in themselves most useful to the student, and at the same time most easily taught. It is also doubted by many instructors, whether Conversations is the best form for a book of instruction, and particularly on the several subjects embraced in a system of Natural Philosophy. Indeed, those who have had most experience as teachers, are decidedly of the opinion that it is not; and hence we learn, that in those parts of Europe where the subject of education has received the most attention, and consequently where the best methods of conveying instruction are supposed to have been adopted, school books in the form of conversations are at present entirely out of use. The author of the following system hopes to have illustrated and explained most subjects treated of, in a manner so familiar as to be understood by the pupil, without requiring additional diagrams, or new modes of explanations from the teacher. Every one who has attempted to make himself master of a difficult proposition by means of diagrams, knows that the great number of letters of reference with which they are sometimes loaded, is often the most perplexing part of the subject, and particularly when one figure is made to answer several purposes, and is placed at a distance from the explanation. To avoid this difficulty, the author has introduced additional figures to illustrate the different parts of the subject, instead of referring back to former ones, so that the student is never perplexed with many letters on any one figure. The figures are also placed under the eye, and in immediate connexion with their descriptions, so that the letters of reference in the text, and those on the diagrams, can be seen at the same time. In respect to the language employed, it has been the chief object of the author to make himself understood by those who know nothing of mathematics, and who indeed had no previous knowledge of Natural Philosophy. Terms of science have therefore been as much as possible avoided, and when used, are explained in connexion with the subjects to which they belong, and it is hoped, to the comprehension of common readers. This method was thought preferable to that of adding a Glossary of scientific terms. The author has also endeavored to illustrate the subjects as much as possible by means of common occurrences, or common things, and in this manner to bring philosophical truths as much as practicable within ordinary acquirements. It is hoped, therefore, that the practical mechanic may take some useful hints concerning his business, from several parts of the work. Hartford, May, 1830. RECOMMENDATIONS. The attention of Teachers, and other gentlemen interested in education, is requested, to the following notices of this "System of Philosophy," which are from the most respectable sources: From John Griscom, LL. D. Principal of the New-York High School. ESTEEMED FRIEND, I have received and examined thy book on Natural Philosophy, with much satisfaction; I have no hesitation in saying, that I consider it better adapted to the pur. poses of School Instruction, than any of the Manuals hitherto in use with which I am acquainted. The amiable author of the Conversations threw a charm over the different subjects which she has treated of, by the interlocutory style which she adopted, and thus rendered the private study of those Sciences more attractive; but this style or manner, being necessarily diffuse, is not so well adapted to the didactic forms of instruction pursued in Schools. Hence also, more matter can be introduced within the same compass, and I find, on comparing thy volume with either of the editions of the Conversations now in use, that the former is much better entitled to the appellation of a System of Natural Philosophy, than the latter. The addition also of Electricity and Magnetism, is by no means unimportant in a course of instruction in the Physical Sciences. I am, with great respect, JOHN GRISCOM. P. S. I have recommended thy book to all the pupils of our High School, who at tend to Natural Philosophy, and it is the only Book which we shall now use as a Class Book. From H. Potter, Professor of Mathematics and Natural Philosophy, in Washing ton College, Hartford, Conn. DEAR SIR, I have examined a portion of your work on Natural Philosophy, and am happy t say that I am, in general, well pleased with the plan you have adopted. With the exception of a few errors, which will doubtless be corrected in a subsequent edition, your mode of treating your subjects seems to be sufficiently scientific for a work so very elementary in its character-and at the same time, it is so popular, as to present few difficulties to an uneducated person of ordinary understanding. The diagrams are generally well drawn, and the plan of introducing them on the same page with the explanation, will contribute greatly to the comfort and advantage of your readers. Very truly Yours, H. POTTER. DR. J. L. COMSTOCK. Washington College, July 1, 1830. From the Right Rev. T. C. Brownell, D. D., LL. D., President of Washington College. From a cursory examination of the work, I willingly concur in the above recom mendation. I know of no similar Book, which, for plan and arrangement, is so well calculated for the use of Schools. T. C. BROWNELL. DR. J. L. COMSTOCK. |