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TABLE OF CONTENTS.

CHAPTER I.

GENERAL OUTLINE OF THE SYSTEM OF CARRYING ON A TRIGONOMETRICAL SURVEY

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CHAPTER II.

MEASUREMENT OF A BASE LINE.

Description of the different Methods that have been adopted to ensure its correct Measurement.-Combined Iron and Brass Rods used on the Ordnance Survey.-Visual Contact with reading Microscopes.-Reduction of a Base measured on any elevated Plain to its Value at the Level of the Sea.-Prolonging and verifying a Measured Base by Triangulation.

CHAPTER III.

TRIANGULATION.

Choice of Stations.-Method of rendering distant Stations visible-by Reflection of the Sun's Rays-Argand Burners-Drummond's Light.— Method of increasing the Length of the Sides of the first Triangles directly from the Measured Base.-Secondary Triangles.-Assumed Base.-Instruments used for observing Angles on the Continent and in England.—Reduction to the Horizon.-Spherical Excess.-Reduction to the Centre.— Adjustments of a Theodolite.-Method of discovering lost Stations.— Laying down a Triangulation upon Paper.-Position of Trigonometrical Stations also ascertained by astronomical Observation

CHAPTER IV.

INTERIOR FILLING-IN OF A SURVEY, EITHER ENTIRELY OR
PARTIALLY, BY MEASUREMENT.

Method of Filling-in the Detail entirely by Measurement, as practised on the Ordnance Survey.-Levelling Marks and Forms of Field-Books, &c.— Measurement of Roads by the Chain and Theodolite.-Computing the Contents of Enclosures directly from the Field-Book.-Filling-in the Interior, partly by Sketching.-Road Surveying.-Variation of the Compass.-Sketching between Trigonometrical Points and Measured Lines.— Practical Methods of avoiding Obstacles and determining inaccessible Heights and Distances in the Field.-Station Pointer.-Surveys for Railways

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CHAPTER V.

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Difference between the Objects in view in the Survey of a Cultivated

and that of a new Unsettled Country.-First Operations.-Preliminary Ex-

ploration.-Objects to be principally considered.-Sites of Townships.—

Main Lines of Communication.-Guides for marking on the Ground the

Divisions of Properties.-Size of these Divisions.-Precautions to be ob-

served to secure to the Public Rights of Road, &c.—Necessity for Extensive

Surveys on the First Settlement of a New Colony.-Deviations from Gene-

ral Rules in laying out Sections.-Frontages on, and Access to Rivers and

Main Roads.-Sectional Roads.-Monopoly of Water to be guarded against.

-Sections laid out in Broken Irregular Ground.-Statistical and other In-

formation to be fully afforded to Settlers.-Marking Boundaries of Sec-

tions and Roads.-Reservation of Rights of Road.-Natural Features of

Ground.-Geological and Mineralogical Specimens, and Meteorological

Register, &c.—Usual Method of marking Regular Figures upon the Ground.

-Necessity for a Triangulation to conduct these Operations with any degree

of accuracy when upon an extended Scale.—Advantage of Carrying it on

rather in advance of the Sectional Surveys.-Other Uses of the Triangula-

tion.-District Surveyors.-Surveying by Contract.-Rate of Progress and

Cost per Acre of the Sectional Survey and Marking out Roads.—Cost of

the Triangulation.—Method of Survey pursued in the Canterbury Settle-

ment, New Zealand.-Temporary Division of Land for pastoral Purposes.

—Territorial Division of Counties, Hundreds, &c.—Remarks on Exploring

Expeditions.-Method of Proceeding.-Objects in View, and collateral In-

formation to be obtained

IV. TO FIND THE LOCAL TIME.

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