Olmsted's Introduction to JVatural Philosophy. 353 



to be used as a class-book than any other similar work. Cavallo's 

 Elements of Natural Philosophy, and the Treatises of Wood and 

 Vince, have been used in a few of our colleges ; but the diffuse style 

 of the former work, and the absence of practical applications in the 

 latter, rendered them both ill adapted to the purposes of a class-book. 



The late publications at Cambridge by Professor Farrar, compri- 

 sing an entire course of mathematical and philosophical text books, 

 compiled chiefly from the French writers, ably supplied the deficien- 

 cy alluded to, and might seem to have rendered the present work 

 unnecessary. But, for several reasons, the Cambridge Philosophy 

 was found not to be adapted to the course of mathematical and phi- 

 losophical instruction in Yale College ; particularly, as it does not 

 correspond, in its references, to the mathematical works of President 

 Day, which are used in this Institution (and which there is no incli- 

 nation to exchange for any other) and, moreover, it is so extensive as 

 to require a greater amount of time, than can be spared for this pur- 

 pose consistently with the other exigencies of the Philosophical de- 

 partment, and with the claims of the other departments of instruction. 



The general design of Professor Olmsted's work, is expressed in 

 the preface. It is, " first, to make the student thoroughly and fa- 

 miliarly acquainted with the leading principles of Natural Philoso- 

 phy, and, secondly, to furnish him with as much useful information, 

 as possible, within so limited a compass." In prosecuting the form- 

 er design, the compiler has first confined the attention of the student 

 to the " Mathematical Elements," comprising a selection of the most 

 important principles in the science of Mechanics ; — principles which, 

 on account of the universality of their application, are particularly 

 worthy of standing in the fore-ground of Natural Philosophy, and of oc- 

 cupying for a considerable time the undivided attention of the student. 



Under the impression that the interest felt in the investigation and 

 contemplation of abstract truths, like those of pure geometry, and 

 theoretical mechanics, is, in its nature, different from that derived 

 from pursuing these truths into their practical applications, and even 

 that the two kinds of interest are in some degree incompatible with 

 each other, the practical part of Mechanics is entirely separated from 

 the theoretical, and made to constitute Part II, of the first volume. 

 Two incidental advantages, also, result from this arrangement; — the 

 first is, that the second part furnishes an excellent general review of 

 the principles of Mechanics, in their connexion with each other j and 

 the second is, that in the explanation of the phenomena, either of 



Vol. XXIII.~No. 2. 45 



