MENSURATION, MECHANICAL POWERS, AND MACHINERY. THE PRINCIPLES OF MENSURATION ANALYTICALLY EXPLAINED, AND OF THE SIMPLE MECHANICAL POWERS, AND THEIR DESIGNED FOR THE USE OF SCHOOLS AND ACADEMIES. KEENE, N. H.: Educt-1784969 Educ T 198.49.115 ARVARD COLLEGE LIBRARY CHARLES HERBERT THURBER Jul. 26,1927 Entered according to Act of Congress, in the year 1849, by J. HOMER FRENCH, In the Clerk's Office of the District Court of the District of New Hampshire. Stereotyped by NEW ENGLAND TYPE AND STEREOTYPE FOUNDERY, BOSTON. PREFACE. MORE than nineteen twentieths of the children in our country receive all their education in the common schools. And but about one half of the number who attend the high schools and academies, ever go further in a course of mathematical study than through the elements of Algebra and Geometry. Hence, of the whole number of scholars in all the schools in our country, not more than one fortieth ever acquire as much knowledge of the principles of Mensuration as is actually needed for the everyday business of life. Now, this is manifestly wrong. Every person, and more especially every young man, should possess sufficient knowledge of the principles of Mensuration to enable him to transact his business independent of arbitrary rules, or of the assistance of those who, having been more fortunate than himself in acquiring a knowledge of these principles, render the necessary aid only for a stipulated sum. But wherein lies this evil? It is not in the want of treatises upon Mensuration; for the world is well supplied, upon this subject, with textbooks abounding in mechanical rules. Neither is it in the want of facilities for acquiring a thorough mathematical knowledge; for the doors of our high schools, seminaries and colleges, are open alike to all who may choose to enter. The rules and principles presented in most of the textbooks heretofore written upon this department of education, are mere directions for the performance of a mechanical process, which, if followed, will "bring the answer." The reason generally given for thus presenting them is, that the principles involved cannot be understood without a thorough knowledge of Geometry. But this is not so. A great majority, nay, nearly all of the rules and principles involved in Mensuration as applied to the actual business of life, admit of an analysis perfectly comprehensible by the mere arithmetician. The evil must be, then, in the want of the proper kind of text-book; one that shall give the why, as well as the how; one that shall be adapted to the capacity of the student who has no knowledge of mathematics beyond Arithmetic. Such a work, it is believed, is here presented to the public. The characteristics of the work are the following: |