Surveying, as Practiced by Civil Engineers and Surveyors ...: Intended as a ... - John Whitelaw - Google Books

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SURVEYING WITH THE AID OF ANGULAR

Instruments: Theodolite- Everest Theodolite - Plain Theodolite-

Vernier-Circumferentor or Surveying Compass-Whitelaw's Theo-

dolite and Mining Dial-Sextant-Box Sextant-Use of Box

Sextant-Theory of the Sextant - Measuring Angles with Box

Sextant when Ground is not Level-Prismatic Compass-Pocket

Compass-Plane Table-Range Finders: The Labbez Telemeter-

The Weldon Range Finder-The Bate Range Finder--Care of

Instruments-Trigonometrical Formula for the Solution of Plane

Triangles-Right-angled Triangles-Oblique Triangles - General

Trigonometrical Formula-Measuring Angles with the Theodolite

-Method of Repetition-Using both Faces of the Instrument—

Accurate Method of setting Instrument in Line-Method of con-

ducting an Ordinary Small Survey with the Theodolite - Field

Book-Reconnaissance of Ground-Practical Hints-Obstacles to

Measuring-Crossing a River-Example of an Ordinary Small

Survey with the Theodolite-Traverse Surveying-Example of an

Unclosed Traverse Survey-Ordinary Method of taking Bearings

-Method of avoiding Errors of Adjustment of Instrument in

taking Bearings--Plotting by Distances and Bearings with Pro-

tractor-Latitudes and Departures-Example of Calculation of

Latitudes and Departures-Traverse Tables-Example of Use of

Traverse Tables-Plotting by Latitudes and Departures-Checks

on Unclosed Traverse-Example of Closed Traverse Survey-

Checks on Closed Traverse-Checks on Plotting of Closed Traverse

-Graphic Adjustment of Closing Error-Adjustment of Closing

Error by Calculation-Example of Adjustment of Closing Error

by Calculation-Adjustment of Closing Error when some of the

Measurements may be considered more accurate than others—

Adjustment of Closing Error when the Error is considered to

be due to the Chaining only-Amount of Closing Error allow-

able in practice-Compass Traverse Surveys-Variations of the

Compass: Annual Variation-Diurnal Variation-Dip of Magnetic

Needle-Local Attractions-Town Surveys: Example of Town

Survey-Surveying with the Box Sextant-Surveying with the

Prismatic Compass-Instruments for Approximate Measurement

of Distances-By a 2 ft. Rule-Perambulator-Pedometer and

Passometer-Trocheameter-Example of Prismatic Compass and

Passometer Survey - Surveying with the Pocket Compass

Surveying with the Plane Table - Photographic Surveying -

Advantages of the Photographic Method of Surveying — Field

Work-Office Work-Levels -- Contours by Photographic Sur-

veying-Cost of Photographic Surveying Plotting the Survey:

Protractors-Section Paper - Computation of Areas: Areas of

Triangles-Calculation of Area of Closed Polygon from Lengths
and Bearings-To Cut Off a Given Area by a Straight Line Start-
ing from a Given Point in the Boundary of a Survey-To Cut Off
a Given Area from a Survey by a Straight Line with a Given
Bearing

PAGES

60-126

CHAPTER III.

LEVELLING.

--

Instruments: Water Level-Spirit Level-Radius of Curvature of
Bubble Tube-Sensibility-Accurate Measurement of Small Vertical
Angles by means of Bubble Tube of Spirit Level-Angular Value
of one Division of Bubble Tube-Measurement of Small Angles
with Bubble Tube-Circular Spirit Level-Dumpy Level-The Y
Level-Levelling Staff-Levelling with the Spirit Level: Detached
Levels Continued Series of Levels-Field Book: "Rise and Fall"
System-Booking the Levels-Reducing the Levels-Check on
Reducing the Levels-Datum-Bench Marks-Reduced Levels—
Plotting the Levels: Longitudinal Section-Readings near Top
of Staff-Field Book: "Collimation" or 66 Height of Instrument"
Method-Intermediate Sights-Comparison of "Rise and Fall"
and "Height of Instrument" Systems-Example of Longitudinal
Section-Example of Level Book-Cross Sections-Checking
on to Bench Marks or 'Checking Back"- Hand Level-
Clinometer Cross Sectioning with the Clinometer Cross
Sectioning with the Theodolite - Contours - Vertical Distance
between Contour Lines - Determination of Contour Lines -
Second Method-Interpolation of Contours-Graphic Method of
Interpolating in Contours-Ridge and Valley Lines-Sketching
and Inking in Contours-Calculation of Contents from Contour
Lines Delineation of Ground by Hatchings — Delineation of
Ground by Shades from Light Falling Vertically - French
Method-German Method or Lehmann's Method-Delineation of
Ground by Shades from Light Falling Obliquely-Correction of
Levels for Curvature - Refraction-Other Instruments: Plumb
Line Levels-Reflecting Levels-Boning Rods-Practical Hints,
Obstacles and Difficulties-Change Points-Steep Slopes-Levelling
Across a Hill-When the Staff is too low or too high-When the
Staff is too near to read the Divisions-Board Fence-Wall-House
-Sun-Personal Error-To Locate a Given Level-Reciprocal
Levelling-Hypsometry or Levelling with the Barometer-Correc-
tion for Temperature of Mercury-Correction for the Temperature
of the Air-Correction for Latitude-Correction for Height of
Lower Station-Correction for Decrease of Gravity on a Vertical-
Mercurial Barometric Tables-Example of Use of Tables --French
Barometers-Babinet's Simplified Formula-Belville's Short Ap-

-

proximate Rule-Heights by Aneroid Barometer-Aneroid Baro-

metric Tables-Accuracy of Barometric Observations-Determina-

tion of Heights by Boiling Point Thermometer-Boiling Point

Thermometer Tables--Instruments: Aneroid Barometer-Mountain

Barometers-Boiling Point Thermometer-Levelling by Angular

Measurements or Trigonometrical Levelling-Calculation when

Curvature is allowed for-Calculation when both Curvature and

Refraction are allowed for-Reciprocal Observations for Cancelling

Refraction-Reduction of the observed Angles from the Summits

of Signals-Measurement of Heights by Observation to the Sea

Horizon-Precise Spirit Levelling-Instruments: Level-Kern

Level-Levelling Staff-Daily Adjustments—Field Work: Errors

from Unstable Supports-Atmospheric Errors-Available Working

Hours-Observing Staff Readings-Length of Sights-Corrections

-Accuracy and Cost of Precise Spirit Levelling-Adjustment of

Errors in Closed Circuits of Precise Levels-American Practice in

Precise Spirit Levelling--Value of one Division of the Bubble Tube

-Correction for Inclination of Bubble to Upper Surfaces of Rings-

Correction for Collimation Line-Correction for Inequality in the

Size of the Rings-Final Correction-Instructions for Precise Spirit

Levelling under the Mississippi River Commission

ADJUSTMENT OF INSTRUMENTS.

Chain-Theodolite--Temporary Adjustments-To Set up the Instru-

ment over a Station--To Level up the Instrument-Focussing the

Object Glass and Eyepiece-Permanent Adjustments-Adjustment

of the Supports of the Horizontal Axis of the Telescope —Adjust-

ment of the Collimation Line-Accurate Method of Adjusting the

Collimation Line of Transit Theodolite-Adjustment of the Level

on the Telescope-Index Error of Vertical Circle-Centring of the

Object Glass and Eyepiece-Adjustment of the Diaphragm Ring

so that the Cross Hairs are truly Vertical and Horizontal-To

Replace the Cross Hairs-To Replace a Spirit Level or Bubble

Glass - Adjustment of the Sextant - Adjustment of the Box

Sextant-Adjustment of the Compass-To make the Needle truly

Horizontal-To make the Sights Perpendicular to the Compass

Plate-To Straighten the Needle-Adjustment of the Pivot Pin-

Pocket Magnifier-Magnetic Attraction about the Person-Sight

Slits-Remagnetising the Needle-Adjustment of the Level-To

make the Collimation Line coincide with the Axis of the Telescope

To make the Spirit Level parallel to the Collimation Line-To

make the Telescope and Spirit Level together Perpendicular to the

Vertical Axis, or to make the Instrument " traverse"-Adjustment

RAILWAY (INCLUDING ROAD) SURVEYS AND SETTING OUT.

Home and Foreign Work-Parliamentary Surveys-Ordnance Survey

Maps Special Local Considerations Ruling Gradient and

Minimum Radius of Curve-Laying down Line on 6 in. Ordnance

Map-Fixing Gradients-Reconnaissance and Sketching in Loca-

tion on Map-Plotting Sketched Location--Levelling the Longi-

tudinal Section-Correcting the 6 in. Ordnance-Referencing—

Preparation of Parliamentary Plans-Preparation of Parliamentary

Sections-Parliamentary Estimate-Board of Trade Regulations

for Light Railways-Example of Parliamentary Plan and Section

of Railway taken from actual practice-Working Surveys-

Revising and Improving Parliamentary Location-Final Location

of Line in Difficult Country-Pegging out Line-Pegs-Tangent

Points-Chainages and Survey of Existing Detail—Longitudinal

Section - Cross Sections - Working Plan-Working Section-

Fixing Gradients on Working Section-Levels on Working Section

-Cuttings and Banks on Working Section-New Works and

Existing Details on Working Section-Examples of Working Plan

and Working Section of Railway taken from actual practice-

Kuling Gradients-Train Load-Speed-Locomotive Power and

Train Resistance-Maximum Gradient-"Pusher" Gradients--

Minimum Radius of Curve-Compensating Gradients on Curves-

Cost of Line, Light Railway-Details of the Field Work of Working

Survey and Pegging out: Instruments-Steel Band and Tapes-

Ranging Rods, &c.—Chainmen-Pegging out Centre Line --Chain-

ages and Survey of Detail-Bridges--Setting out Curves --Calcula-

tion of Length of Tangents-Calculation of Deflection Angles-

Exact Formula for Calculation of Deflection Angles-Calculation

of Length of Curve-Chainage of Tangent Points and Deflection

Angle for each Peg on Curve-Check on Calculation of Deflection

Angles-Laying off the Deflection Angles and Putting in Pegs on

Curve-Check on Laying off the Deflection Angles - Check on

Chaining Round Curve-Final Error in Setting out Curve-Con-

tinuing Work after Setting out Curve –Chaining to be "through'

--Shifting the Instrument forward to Intermediate Point on

Curve Curve to Left - Transition Curves-Froude's Curve of

Adjustment-Setting out Transition Curves-"Cant "-Transition

Curves between Reversed Curves Vertical Curves at Changes

of Gradient-Setting out of Work during Construction: Transfer-

ring Tangent Points-Setting out Fence Widths-Levelling in

Tops and Bottoms of Slopes-Setting out Bridge and Culvert

Foundations-Setting out Culverts-Setting out Bridge Abutments

-Other Setting out: Centre Lines and Levels in Cuttings and

Banks-"Boning Rods"-" Crossheads "-Allowance for Shrink-

age and Settlement-Bench Marks and Checking through Levels-

To Locate a Given Level

TACHEOMETRY OR STADIA SURveying.

Tacheometry-Principle of the Stadia-Distance and Height Measure-

ment by Simple Vertical Angles-Bell-Elliott Tangent Reading

Tacheometer - Barcenas' Tangential Method - Principle of the

Tacheometer-Distance apart of Stadia Hairs--General Rules in

Stadia Work-Methods of Determining Distance apart of Stadia

Hairs and other Constants-Porro's Stadia Telescope-Troughton

& Simms' Tacheometer-Specially Graduated Staff-Stadia Tables

for Horizontal Sights-Inclined Sights: Staff held Vertical—

Inclined Sights: Staff held Perpendicular to Line of Sight-Errors

in Distance and Level with Staff held Perpendicular to Collimation

Line - Error from badly held Staff — Tables for making the

Reductions Stadia Table for Inclined Sights- Reducing the

Levels For Back Sights-For Fore Sights-Field Book-Field

Work-Micrometer for Long Sights-Best Class of Instrument for

Tacheometry-Office Work-Special Protractor - Accuracy of

Tacheometry or Stadia Surveying-Tangential System - Subtense

System-Comparison of the two Systems-Levelling-American

Practice in Tacheometry or Stadia Surveying — Example of

Tacheometer or Stadia Survey

TUNNEL ALIGNMENT AND SETTING OUT.

Surface Alignment-Surface Alignment over Hills--Example of Surface

Alignment over Hills: Alignment of the Totley Tunnel-The

Alignment Aboveground—The Alignment Underground - Surface

Alignment in Towns-Instruments for Setting out Tunnels-Setting

out Curves in Tunnels-Taking Measurements-Observing Angles

-Marking Centre Line on Surface-Traversing between Shafts-

Transferring Surface Line down Shafts-Setting out Underground

Line-Marks for fixing Underground Line-Transferring Surface

Line down Shafts when Plumb Bobs cannot be used—Underground

Sights and Lamps-Illuminating Cross Hairs of Telescope-Ar-

rangement for Sighting on Wires Suspended in Shaft-White

Reflectors to Verniers-Alignment of the Mersey Tunnel-Align-

ment of Dunmail Rise Tunnel on Thirlmere Aqueduct—Examples

of Errors in Alignment of Long Tunnels-Levels-Transferring

Levels down Shafts - Underground Bench Marks - Checking

Underground Levels and Centre Line through between Shafts-

Setting Ribs and Profiles--Setting Segments of Iron-lined Tunnels

-Taking Level of "Crown" of Tunnel-Alpine Tunnels: Mont

Cenis Tunnel-St Gothard Tunnel--The Arlberg Tunnel-Pro-

jected Alpine Tunnels-Mont Blanc Tunnel-Great St Bernard

Tunnel-Simplon Tunnel

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