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MECHANIC'S, MACHINIST'S, AND ENGINEER'S
CANTAINING TABLES AND FORMULÆ FOR USE IN SUPERFICIAL AND SOLID
CHEMISTRY AND MISCELLANEOUS RECIPES.
FONTAINING FORMULA FOR THE VARIOUS METHODS OF RUNNING AND CHANGING
LINES, LOCATING SIDE TRACKS AND SWITCHIES, &C., &r.
NATURAL SINES AND TANGENTS TO EVERY DEGREE
AND MINUTE OF THE QUADRANT,
LOGARITHMS OF NATURAL NUMBERS FROM 1 To 10,000.
BY CHARLES HASI ETT,
EDITED BY CHARLES W. HACKLEY,
Professor of Mathematics in Columbia College, NY
4C WALKER STREET.
Entered according to the Act of Congress, in the year 1855, by
STRINGER & TOWNSEND,
In the Clerk's Office of the District Court of the United States for the Southern
District of New York.
No more useful little works have ever been presented to the public than the various pocket companions of a character analogous to that here offered. These have been a good deal, though not yet too much, multiplied of late; and where the formulas, rules, and tables which they contain have been skilfully framed under the guidance of scientific men, they have afforded to the Practical Engineer, Architect, and Mechanic, the most welcome aid in the constructions and computations which make part of their daily oocupation, and which, without the ever-at-hand suggestions and directions of these unpretending little servants, might consume hours and days in the turning over of large volumes, or in painful investigations based on general principles of science where the individual happened to be competent to conduct them.
The wants to be supplied in such a work are discovered by experience and observation in the different callings for which they are more especially intended. That these wants have not all been met in the works of a similar kind which have already appeared will be made evident by a simple inspection of the amount and variety of new matter contained in the present volume.
It is not every one, however practically expert he may be in his own pursuit, that is capable of arranging and digesting in the best manner the knowledge necessary for his own use which he may have been years in acquiring, so as to reccel y available for the use
of others. Such a task, to be well performed, requires a bination of mental qualities not always, perhaps not often, found in the same individual.
A happy concurrence of circumstances has by accident secured for the composition of the present work the labors of several skilful hands, both as compilers from the best foreign sources, and as original producers of valuable material never before in print. The result of so much well directed industry is the rich collection, not a line of which is not invaluable, which, in the aptest form for immediate use, has been crowded into the space of a single small volume.
Steam and its application play so important a part in the economy of life at the present day, that the most useful practical rules and formulas for all the ordinary cases occurring, cannot with propriety be omitted in a work of this kind. A due attention will be found to have been paid to the matter, and some of the newest modes of managing in steam supplied with the means of the requisite computation.
The laying out of Railroad curves is one of the most important and at the same time laborious and troublesome duties which the Civil Engineer has to perform. So much of this occurring on every line of Railroad, any, however slight, improvement of method which may serve to facilitate or lessen the labor of this process is a real boon to that large and eminently useful and accomplished body of men to whom the supervision of such operations is committed.
The use of the more common trigonometric functions, to wit, sines, cosines, tangents, and cotangents, which ordinary tables furnish, is not well adapted to the peculiar problems which are presented in the construction of Railroad curves. The additional columns of secants and cosecants in the tables of Dr. Bowditch sometimes afford a slight additional facility, which would be much increased had we also columns of natural secants as well as logarithmic.
Still there would be much labor of computation which may
be saved by the use of tables of external secants and versed sines, which have been employed with great success recently by the Engineers on the Ohio and Mississippi Railroad, and which, with the formulas and rules necessary for their application to the laying down of curves, drawn up by Mr. HASLETT, one of the Engineers of that Road, are now for the first time given to the public. This portion of the volume alone, by the great abridgment of labor for which it provides the means, and the simplicity and convenience of the matter which it furnishes, will give it an extensive circulation among Practical Engineers.
But besides this, the Architect, the Shipbuilder, the Mason, the Carpenter, the Joiner, the Manufacturer and Artisan in iron and every species of material, will find rules and recipes for all kinds of estimates, computations, constructions, compositions, mixtures, et cetera, which will excite surprise at their number, novelty, and value to every one.
The contents of this volume are of so varied a nature that it was not deemed necessary to make any strenuous efforts to arrange them systematically. Being solely intended for a book of reference, the relative order of the subjects is immaterial; and the copious Table of Contents and Index afford all the assistance that can be desired by those who wish to consult its pages.