ENGINEERS' SURVEYING INSTRUMENTS.

BY HELLER & BRIGHTLY.

CONTENTS.

Published by HELLER & BRIGHTLY,

S. E. Cor. Spring Garden & Ridge Ave.,

TA581

ΤΟ

OFFICE OF HELLER & BRIGHTLY,
PHILADELPHIA, February, 1874.

THE ENGINEERING PROFESSION.

37943

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When we some three years since first introduced our " Improved Transit " to the Engineering profession, we had no idea that it would meet with so immediate favor as it has, especially as we made no particular efforts to spread the knowledge of the improvement. The first public knowledge was conveyed through the paper_read before the American Philosophical Society by J. PETER LESLEY, Esq., Dean of the Faculty of the new Department of Science of the University of Pennsylvania, as well as Professor of Mining and Geology in that institution; than whom no person is better qualified by extensive practice in the field to judge of the quality of Surveying instruments. On the publication of this paper, we resolved to submit our instruments to a committee of experts to be appointed by the Franklin Institute of Philadelphia. This committee was composed of the following gentlemen: JNO. C. TRAUTWINE, Civ. Eng., author of the " Engineers' Pocket-Book," works on "Excavations," Curves," etc., and whose knowledgs regarding all matters connected with Civil Engineering is too well known to need recapitulation, was Chairman; SAML. L. SMEDLEY, Chief Engineer and Sur veyor of the city of Philadelphia; CHAS. S. CLOSE, Esq., of the Philadelphia Survey Department; L. M. HAUPT, Civ. Eng., Prof. of Civil Engineering in the University of Pennsylvania; and ELLWOOD MORRIS, Civ. Eng., author of "Earthworks," formerly Chief Engineer of the Ohio and Chesapeake Canal, and of other works, being the remaining members. After a thorough examination in whole and in detail of the instruments and the principles of their construc tion, they unanimously made the report that will be found in the body of the pamphlet. In proof of the sincerity of the opinions of each individual member of the committee, we may state that since the report was submitted, the Survey Department of the city have procured from us all the new instruments required since that date, amounting to eight in all; also that the University of Pennsyl vania have purchased from us all the Engineering instruments required by that institution; and, moreover, we have sold instruments either to every member of the committee directly, or to other Engineers at their recommendation.

As we have in the last three years made two improvements in Telescopes, a word of explanation may be necessary to distinguish them apart. In 1870 we improved the formula in general use for Telescopes in such a manner as to practically annihilate the chromatic and spherical aberration. This Telescope is the one referred to in the Philosophical Society paper, and in the report of the Franklin Institute Committee of Civil Engineers; and this Telescope is on all of our instruments from No. 4100 to No. 4592 inclusive. (All of our instruments are numbered on the face.)

Early in 1873 we commenced experimenting in order to increase the power of our Telescopes, and we only brought our experiments to a perfectly satisfactory conclusion in the latter part of December of the same year. We have made but comparatively few instruments with this new Telescope attached (from No. 4593 to 4645 inclusive). This latter Telescope is, however, the one which we are now placing on all of our new instruments; and it was with a Telescope of this kind on a Transit that we made for the City of Philadelphia Survey Department, that the comparisons as to power, range and definition, as compared with an ordinary Transit Telescope, were made by Mr. Stauffer.

The articles extracted from the editorial columns of the United States Railroad and Mining Register will give the full details concerning the "Improved Telescope;" and the "Franklin Institute Report" first sees the light in these pages. Having within a short time doubled our force of skilled workmen and tools, and having also called in the aid of steam, we hope in the future to supply any reasonable demand on us for instruments, and to avoid the vexatious delays that we heretofore frequently have had to subject our friends.

OFFICE OF HELLER & BRIGHTLY,}

PHILADELPHIA, June, 1875.

To the Engineering profession we herewith present the fourth edition of our pamphlet, materially enlarged and, we hope, improved. Through the kindness of Mr. Trautwine we are enabled to give all the errors that have been detected in his "Civil Engineer's Focket Book." For the privilege of inserting the valuable sheet of "Topographical Conventional Signs" we are indebted to Prof. Haupt, of the University of Pennsylva nia, the following letter from whom we insert.

1807 CHRISTIAN ST., PHILADELPHIA, Nov. 30, 1874.

MESSRS. HELLER & BRIGHTLY:

GENTLEMEN.-Having for many years felt the necessity for a set of Conventional Signs for Topographical Engineers which should be condensed and accurate, I have compiled the accompanying chart for use in the University of Pennsylvania and the Engineering profession in general, believing that it will supply a long-existing want in this class of information.

They are compiled from the best American and English authorities and carefully classified, making any explanations superfluous.

Yours, very respectfully,

LEWIS M. HAUPT, Professor Civil Engineering.

PREFACE TO THE SIXTH EDITION.

January 1, 1876.

Through the kindness of Prof. Haupt and of the Civil Engineering section of the Class of 76 of the University of Pennsylvania, we are enabled to give in the present edition the valuable plate, "Study in Contours," and its explanatory description.

PREFACE TO THE FOURTEENTH EDITION.

In this our fourteenth edition we hope our friends will find fresh matter of interest. We have endeavored to make this pamphlet of more value than merely as a pricelist, and we think our efforts have not been in vain, from the fact of its having been (on account of its Table of Topographical Signs, Topographical Contours, etc.) adopted as an auxiliary class-book in eight colleges. The table of express charges on engineering instruments to or from any part of the United States, and the method of sending parts of instruments by mail, will also be found of value.

We must apologize for the typography, binding, etc., of the seventh, eighth, ninth, tenth, and eleventh editions, as the demand for it from visiting Surveyors and Engi neers during and after the Centennial year required us to furnish the pamphlet rather quicker than was consistent with good printing (four editions were called for during the Centennial year, we having distributed an average of one hundred copies daily at our exhibit in the Main Building).

As we have made several changes in our prices, the present Price List (to be found at the end of the book) will supersede all others.

PHILADELPHIA, May, 1878.

HELLER & BRIGHTLY.

MESSRS. HELLER & BRIGHTLY.

UNIVERSITY OF PENNSYLVANI
Philadelphia, Nov. 20, 1875.

GENTLEMEN: In compliance with your request I have prepared a reduced plot to show the method of representing topography by means of contours. As such information can only be intended for amateurs, I will explain the method in detail and show some of its applications to location.

If a series of horizontal planes be assumed at equal distances apart, they will intersect an irregular or inclined surface in lines; or if a water level be supposed to be raised or lowered by equal stages, the successive water-lines or edges thus formed will represent the contour lines of the surface. These contours or horizontal sections are shown by projecting them upon a horizontal plane.

In the case in question, the lowest point of the field was found, and the horizontal plane passing through it assumed as the zero or datum plane, upon which all the other contours were projected. The interval between the planes was assumed to be three feet, and the points on the surface at these various elevations, having been first determined by the level and rod, were located by the plane table.

This method of representing topography is vastly superior to any other, as it exhibits exactly the slope at any portion of the ground; gives the elevation of the base of any object within the tract; enables one to make vertical sections in any direction with accuracy from the plot, and to locate roads, paths or other features upon a given grade or at any desired elevation, and furnishes the means of calculating the contents of irregular solids with great precision.

To locate a road upon a given grade, say--180: take with the dividers from the scale one hundred feet, and starting from a given point—say P— describe an arc from it as a centre, cutting the next lower contour (27) from this intersection as a centre; with the same radius describe an arc cutting (24), and so on. The line joining these centres will be a surface-line on the given grade, and will be the cheapest road that can be built upon the given conditions. Crossing the stream at (T T'), upon a level 6′ above the water, to reach the top of the hill at V the grade must be increased to 150 or 2; and the centre line is located in the same manner, but with a radius of 60′, as that will be the base for a rise of three feet. Descending from V to W, the grade is the same; but from W to X it is reduced to 250 or 4, to prevent cutting at X. From Z back to P two routes are shown, which are the shortest for the given grade 18, although a third might be located following the stream to a point M, where it must be diverted to N, and thence zigzag up the hill, but it would be longer than the others. The two distances Zxyz SR and Zx'y'z' R are equal; but the first gives a more graceful curve and will require less construction, the part SR being supposed to have been already built for the descending grade.

These are a few of the applications of this system of projections. It is also of great use in dividing up land, computing areas, locating a system of drainage, etc.

Yours very truly,

LEWIS M. HAUPT,

PROF. OF CIVIL Engineering.