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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

118

b

IV.-TO FIND THE LOCAL TIME.

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No. 4. CONTENT PLOT AND DIAGRAM-ditto.
No. 5. SCALE OF SHADE FOR REPRESENTING SLOPES OF GROUND,

-to face page 60. No. 6. ANAGLYPTOGRAPH ENGRAVING FOR TOPOGRAPHICAL DRAW

ING—to face page 117. No. 7. SPECIMENS OF THE VERTICAL AND HORIZONTAL STYLE OF

SKETCHING GROUND—to face page 59.

No. 8. METHOD OF TRACING CONTOURS

}

to face page 95, &c.

No. 9. SPECIMEN OF CONTOURING

AND 113 WOOD-CUTS.

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The basis of an accurate survey, undertaken for any extensive geodesical operation, such as the measurement of an arc of the meridian, or of a parallel, or the formation of a geographical or territorial map, showing the positions of towns, villages, &c., and the boundaries of provinces and counties, or a topographical plan for military or statistical purposes, must necessarily be an extended system of Triangulation, the preliminary step in which is the careful measurement of a base line on some level plain :-at each extremity of this base, the angles are observed between several surrounding objects previously fixed upon as trigonometrical stations; and also, when practicable, those subtended at each of these points by the base itself. The distances of these stations from the ends of the base line and from each other are then calculated, and laid down upon paper, forming so many fresh bases from whence other trigonometrical points are determined, until the entire tract of country to be surveyed is covered over with a net-work of triangles of as large a size as is proportioned to the contemplated extent of the survey, and the quality and power of the instruments employed. Within this principal triangulation secondary triangles are formed, and laid down in like manner by calculation; and the interior detail is filled up between

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