MANUAL

OF

SURVEYING FOR INDIA,

Detailing the Mode of Operations

ON THE

Revenue Surveys in Bengal and the North-West

Provinces.

CHATTER.

Page.

Definition and Properties.-Logarithmical Arithme-
tic-Logarithmic Sines, Tangents, etc.

V. TRIGONOMETRY.

VI.

General Properties of Plane Triangles-Preliminary

Theorems-Solutions of the Cases in Plane Trigo-

nometry, geometrically and by calculation-Applica-

tion of Trigonometry to the ascertainment of Heights

and Distances.

MENSURATION OF PLANES.

......

Definitions-Table of Square Measure-Method of de-
termining the Area of Triangles, Trapeziums, &c.,
and of Irregular Polygons.

VII. USEFUL PROBLEMS IN SURVEYING.

61

66

CHAFTER.

Part EE.

ON SURVEYING INSTRUMENTS.

I. OF THE CHAIN.

II.

Directions for using the Chain-Of the Cross Staff
and Offset Rod-Method of Measuring Offsets-
Of the Perambulator-The Madras Pattern 8-mile
Perambulator-Lieutenant Colonel Everest's 6-mile
ditto-Lieutenant Colonel Waugh's 10-mile ditto.

ON THE PRISMATIC COMPASS.

......

Description of the Instrument and Method of using it

-Of the Surveying Compass-Of the Circumferen-

tor-Of the Plane Table.

110

Construction of the Vernier-Its use- -Of the Theodo-

lite-Its adjustments Lt. Colonel Everest's Pattern

Theodolite-Description of the new Tripod Stand-

Method of Observing with the Theodolite-Hints

on the use of Theodolites.

CHAPTER.

IV.

ས.

Adjustments and method of using the Instrument-
On the Sextant-Principle of its Construction-
Description of the Instrument-Adjustments of
ditto-Of the Artificial Horizon-Method of using
ditto-Remarks on Parallax and Refraction.

ON THE SPIRIT LEVEL.

Page

136

156

Method of testing ditto-The Y Level-On fixing
the line of Collimation-Adjustments-Method of
examining and correcting the Collimation-
Troughton's Level-Gravatt's Level.

VI. THE TRANSIT INSTRUMENT.

Adjustments-Method of observing with the Transit

-Use of the Portable Transit-The Portable Alti-

tude and Azimuth Instrument-Adjustments and

Method of using the Instrument-The Reading

Microscope-Adjustments of ditto-Method of using

Drawing Compasses-Hair Compasses-Compasses
with movable points-Proportional Compasses and
their use-Beam Compass-The Drawing Pen-
The Straight edge-Of Parallel Rulers-The Com-
mon Parallel Ruler-The double ditto-The Cross-
barred ditto-The Rolling ditto.

VIII. ON SCALES...

....

170

191

205

Simple Divided Scales-Diagonal Scales―Their Con-
struction and use-Vernier Scales--On the Pro-
tracting Scales-Construction-Marquois' Scales-
Plotting Scales-Remarks on Scales.

IX. INSTRUMENTS FOR PLOTTING...

Of the Protractor-The Semicircular ditto-The Rec-

tangular ditto-Application of the Protractor to

Use The Circular Protractor-The Circular "Talc"

ditto-The T Square and Semicircular Protractor-

Method of using ditto-The Pentagraph-Descrip-

tion and Method of using the Instrument.

220

IN GENERAL AND FIRST PRINCIPLES... 230

Remarks on Surveys-Hints to Surveyors.

II. ON SURVEYING BY THE CHAIN ONLY.....

The Field Book-Method of keeping ditto-Example

of a Survey by the Chain only.

240

III. ON SURVEYING BY THE CHAIN, ACCOM-

PANIED WITH ANGULAR INSTRUMENTS. 249

Method of determining Angles by the Chain-Example

of a Survey by Theodolite and Chain.

Method of Plotting Bearings-Improved Method-To

lay down the azimuthal angle, subtended between

any Station and the Meridian-Useful Rules ap-

plicable to Geometrical Construction.

V. ON OFFSETS, AND THE VARIOUS PRACTI-

CAL METHODS OF FINDING AREAS, IN-

CLUDING THE REDUCTION OF INCLIN-

ED TO HORIZONTAL PLANES.

......

To find the area of the principal triangles of a Survey
-To find the area of Offsets from a Chain line by
calculation-To find the area of an irregular figure,
by reducing it to a right-lined one of equal contents
-To find the area of Offsets or of an irregular
figure by the "Tale" Square-To construct a "Tale”
Square-Method of reducing inclined to horizontal
distances-Tables for ditto.

VI. ON THE TRAVERSE SYSTEM AND GALE'S

METHOD OF SURVEYING.

Definition of a Traverse-Remarks on the Traverse

System of Survey as compared with Trigonometri-

264

272

CHAPTER.

Page.

cal Surveys-Explanation of the mode of Survey-

ing by Traverse.

VII. ON THE PROOF OF THE TRAVERSE,

AMOUNT OF ERROR ALLOWED AND ME-

THOD OF CORRECTION.

Demonstration of the Proof of a Survey by Traverse

-Amount of error allowed, and mode of distribut-

ing the corrections.

VIII. ON THE METHOD OF PLOTTING BY TRA-

VERSE...............

......

......

......

Method of Plotting-Rule for the reduction of the

Plotting Columns-Remarks on the Method of

plotting by Traverse.

IX. ON THE UNIVERSAL THEOREM.

281

287

...... 291

Demonstration of the Universal Theorem-Case 1st.

-When the Meridian is to the West of the Polygon

and lying entirely out of the Survey-Case 2nd.-

When the Meridian is to the East of the Polygon

and lying entirely out of the Survey-Case 3rd.—

When the Meridian runs through the Polygon-Re-

marks on Case 3rd as invariably to be used in pre-
ference to the 1st and 2nd Cases.

X. ON THE TRAVERSE TABLE.

Explanation of the Columns in a Traverse Table-Tra-

300

verse Table-Computation of the different Columns.

XI. ON THE STRENGTH OF A REVENUE SUR-

VEY ESTABLISHMENT, AND DETAILED

DUTIES OF ITS COMPONENT Parts. 307

Strength of Establishment in the North West Pro-
vinces and in Bengal-Salaries of Assistants and
Sub-Assistants-General duties of a Survey Estab-
lishment-Duties of Assistants, Sub-Assistants, and
of Native Sub-Assistants or Mootsuddees--Duties
of the Revenue Surveyor-Main Circuit Line Cut-
ters, or Tindals, their duties, and method of Pro-
ceeding-Village Line Cutters, ditto-Chainmen,
ditto-Offset Men, ditto-Flag Men, ditto-Instru-
ment Carriers, ditto.