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CONTENTS
INTRODUCTION.
Enumeration of the necessary Drawing Instruments
Description and use of the Protractor.
To measure any angle by the scale of Chords
To erect a perpendicular at the end of a line
To bisect a given line
667 T ∞ ∞ ∞
To let fall a Perpendicular
To bisect a given Angle
when the inclination of the two
sides only can be obtained
9
To draw a Line parallel to a given line
To divide a given line into any number of equal parts
Having three sides given, to construct a Triangle
To describe a Square upon a given line.
To construct a Trapezoid
To construct a Trapezium, having the sides and diagonal
given
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To draw a Tangent to the Circle from a given point in the
circumference
To describe a Circle through three given points.
To find a third Proportional to two given lines
To find a fourth to three
To find a mean proportional between two
To divide a given line into proportional parts
USEFUL THEOREMS
PRELIMINARY OBSERVATIONS.
Value of the Acre
PROB. I.—To bring Acres into Roods and Perches PROB. II.—To bring Chains into Acres
MENSURATION.
To find the area of a Triangle, when the base and perpen-
dicular height are given .
when the three sides are given
To find the area of a Quadrilateral right angled figure
To find the area of a Trapezoid
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To find the area of a parallelogram whose angles are not
right angles
To find the area of a Trapezium
To find the area of an irregular Polygon
To find the circumference of a Circle
To find the Length of an Arc
To find the area of a Circle
To measure a straight line with the Chain
Important Observations to Young Beginners
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26
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CHAP. II.-The Offset Staff
CHAP. III.—The Cross Staff
CHAP. IV.-The Field Book
The Boundaries of Property
CHAP. V.-Survey of a Field of three sides.
of four sides
Example 1.-Field Notes .
Example 1
Example 2
Computation of Acres
by offsets at every chain
by giving and taking, or compensation lines.
Practical Examples of Fields of various shapes, with Field
Notes and Diagrams Plotted to Scale, from No. 1 to
No. 10
Diagram No. 11.-Survey of a River
No. 12.-Survey of a Field from the outside
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CHAP. VI.—Practical Example of Survey of several fields.
Notes.
CHAP. VII.-Explanatory Remarks
Areas
CHAP. VIII.-Reduction of Customary to Statute Measure,
and vice versa.
English Measure.
Different Lengths of the Perch
Modes of taking offsets to houses, &c.—Example 1
. 120
USEFUL AND PRACTICAL PROBLEMS.
To measure a Base Line across a River
To measure the width of a River by a Base Line along side
of it
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. 130
To find the distance of one object from another, where a river
divides them, without using the Theodolite
To carry on the range of a line, when a house or building intervenes
To ascertain the height of an object, when the base is
accessible
When the base is inaccessible, but when DB can be measured
away from the object in a line with the observer and the
object
When the line DB cannot be measured
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. 134
. 135
the length and bearing of a line are given
To find the bearing of a line by the Circumferentor
CHAP. II.—To find the true bearing of a line, the magnetic
bearing and the variation being given
The bearings of two lines being given, to determine the
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angle between them
Practical Example
Check upon the bearings.
CHAP. III.-Surveying with the Circumferentor
Survey of Wood