Of Mensuration, Trigonometry, Surveying, Hydraulics, Hydrostatics, Instruments and their adjustments, Strength of Materials, Masonry, Principles of Wooden and Iron Roof and Bridge Trusses, Stone Bridges and Culverts, Trestles, Pillars, Suspension Bridges, Dams, Railroads, Turnouts, Turning Platforms, Water Stations, Cost of Earthwork, Foundations, Retaining Walls, etc. In addition to which the elucidation of certain important Principles of Construction is made in a more simple manner than heretofore. By J. C. Trautwine, C.E. 12mo, morocco flaps, gilt edges. 28th thousand, revised and enlarged, with new illustrations, by J. C. Trautwine, Jr., C. E. 1887. . . . . . . . . . . . . . . . . . $5 00 "It is the best Civil Engineer's Pocket-book in existence."

- American Engineer.
A METHOD OF CALCULATING THE CUBIC CON-

TENTS OF EXCAVATIONS AND EMBANK-
MENTS BY THE AID OF DIAGRAMS,
Together with Directions for Estimating the Cost of
Earthwork. By John C. Trautwine, C.E. Ninth edition,

revised and enlarged by J. C. Trautwine, Jr. 8vo, cloth, 2 00 THE FIELD PRACTICE OF LAYING OUT CIR

CULAR CURVES FOR RAILROADS. By J. C. Trautwine, Civil Engineer. 12th edition, revised by J. C. Trautwine, Jr. .. 12mo, limp morocco, 2 50

“ Probably the most complete and perfect treatise on the
single subject of Railroad Curves that is published in the

English language."--Engineering News.
THE ECONOMIC THEORY OF THE LOCATION

OF RAILWAYS.
An Analysis of the Conditions controlling the laying out
of Railways to effect the most judicious expenditure of
capital. By Arthur M. Wellington, Chief Engineer of the
Vera Cruz and Mexico Railway, etc. New and improved
edition. . . . . . . . . . . . . . . . 8vo,

5 00 “Mr. Wellington has done great service to the Railroad profession; more particularly to Engineers, Managers, and Superintendents, by bringing together in a single volume such a mass of valuable matter. It should be in every Railway Library."

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A TREATISE UPON CABLE OR ROPE TRACTION.

As applied to the working of STREET and other RAIL-
WAYS. (Revised and enlarged from Engineering.) By
J. Bucknall Smith, C.E. With illustrations and folding
plates. . . . . . . . . . . . . . . 4to, cloth, 2 50

"The publication of this book seems to us to be most
timely. The subject is ably handled by an experienced

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A TREATISE ON CIVIL ENGINEERING.

By 0. H. Mahan. Revised and edited, with additions
and new plates, by Prof. De Volson Wood, With an
Appendix and complete Index. New edition, with chap-
ter on River Improvements by F. A. Mahan. 8vo, cloth, 5 00

"This is the standard text-book on this subject." *** Will be Mailed and Prepaid on the receipt of the price.

Our New Catalogue of 77 Pages for 1890 will be mailed gratis to order.

AND

EXPLORERS' GUIDE.

ESPECIALLY ADAPTED TO THE USE OF

RAILROAD ENGINEERS

ON

LOCATION AND CONSTRUCTION,

AND TO THE NEEDS OF THE EXPLORER IN MAKING

EXPLORATORY SURVEYS.

BY

H. C. GODWIN.

NEW YORK:
JOHN WILEY & SONS,

15 ASTOR PLACE.

hash

File. Souhou

1065012-210

PREFACE.

I Am publishing the following notes because I think they may possibly supply the want of a Field-book,-a want which I have often felt myself and have often heard expressedwhich, while avoiding as much as possible the intricacies of mathematics, would be of more general application than any of the books of this class which I have as yet come across.

The Railroad engineer is rarely an expert mathematician : in fact it has always seemed to me that the time which must necessarily be spent by him in attaining mathematical proficiency might be very much better employed in reading up some of the more practical subjects of his profession. Bearing this in mind, I have endeavored to strip the following pages of all unnecessary mathematical deductions, making it mainly my object to give the results deduced, and yet at the same time giving sufficient explanation to enable any one possessed of the ordinary smattering of mathematics and mechanics to deduce the same results for himself.

I have avoided the insertion of Logarithmic Tables. I am well aware that to some this will appear a serious omission; but considering that this is merely a Field-book, and not a work to be consulted in cases where accuracy in the 6th figure is usually essential, I have deemed that the exclusion of the hundred pages or so which this omission permits, amply compensates for the few seconds of additional labor which the lack of them may occasionally involve. Speaking for myself, as regards Railroad work, I must say that for one time that I work by logarithms I work a hundred times by “naturals ;” and I know that most engineers would bear similar testimony.

In the Astronomical problems in the latter part of the book, considerable labor may, of course, be saved by the use of

Logarithmic Tables. The method I employ myself on such work is to take with me into camp the logarithmic portion of Chambers' Mathematical Tables—which I have had bound in pocket-book form-giving the logarithms of numbers up to 108,000 and of trigonometrical functions to 7 places of decimals: in this way, high accuracy, when it is wanted, can be obtained much more readily and efficiently than by any table which could reasonably be inserted in a book suitable for pocket use; and as the logarithmic tables are rarely wanted outside the tent, they form a sort of stay-at-home counterpart to the Field-book itself.

Table IX is inserted solely for convenience in the reduction of indices, barometric formulæ, etc., and a few like operations, in which the use of logarithms is more or less essential.

H. C. GODWIN. COLORADO, January, 1889.