LONDON:

SAVILL AND EDWARDS, PRINTERS, CHANDOS STREET,

COVENT GARDEN.

CONTENTS.

CHAPTER I.

Gunter's Chain, 2. Chaining, and Practical Observations on the method of Chain-

ing Correctly and with Despatch-Remarks as to "the Leader and the Follower,"

4. Chaining over Sloping Ground-Inclinometer, 9. Offsetting and Offset Staff, 11.

A First Lesson, 14. Stations, 15. Field-book, 16. Straight-edge, 19. Scales, 20.

CHAPTER II.

Chain Surveying, 22. Triangulation, 23. Ranging Rods, 24. Base Lines, 25. Peram-

bulation and Setting Out Base Lines, 26. Suggestions as to First Studies, 29.

Chain Angles-General Rules, 31.

CHAPTER III.

Instruments for Laying Down and Plotting Chain Surveys-Scales, 33. Expansion

and Contraction of Paper-Beam Compasses, 35.

CHAPTER IV.

Geometrical Memoranda, 36. Paper Protractor, 39. Memoranda as to the Properties

of Rectilineal Triangle, 40. The Circle, 42. Rectangles, 44. Setting Out Perpen-

diculars and Parallels on the Ground-Inaccessible Distances, 45. Computation of

Areas and Reduction of Figures, 53.

CHAPTER V.

Surveying Instruments-The Cross Staff and Optical Square, 57. The Prismatic Com-

pass, 58. Use of the Prismatic Compass, 61. The Vernier, 64. Construction of

the Sextant and Box-Sextant, 68. Use of the Sextant, 74. With the Artificial

Horizon, 76. The Box-Sextant, 77. The Transit Theodolite, 80. Adjustments,

83. The Ordinary Theodolite, 85. Everest's Theodolite, 86. Use of the Theodo-

lite, 87.
Repeating Angles, 89. Setting out Bases with the Theodolite, 90.

CHAPTER VI.

Surveying by Traverse, 91. General Observations on Traversing, 93.

CHAPTER VII.

Plotting and Protracting, 96. The Circular Protractor, 97. Howlett's Protractor-

Observations on the Circular Protractor, and Method of Using Howlett's Protractor,

99. Metcalfe's Protractor, 101. Plotting a Traverse by Northings, Southings,

Eastings, and Westings, 103. Application of Northings and Southings, &c., 105.

Application of Trigonometrical Tables to the above, 106. Pocket Trigonometry,

107.

CHAPTER VIII.

Railway, Canal, and Road Surveying, 109. Setting out Bases, 110. Management of

the Survey, 112. Exploring Survey, 115. Canal Survey, 116.

Working Plans, 119.

CHAPTER IX.

Details of Townlands' Survey-Precautions to be Observed,

120. Object and Value of Working Plans, 124.

CHAPTER X.

Ranging Curves Theory, 127. Application of Trigonometrical Tables, 130.

Length of Arc, 135. Examples, 136. The Practice of Ranging Curves, 137.

Reverse Curves, 142. Intersection of Tangents Inaccessible, 144. Curve Inaccessible,

146.

CHAPTER XI.

Variation of the Magnetic Needle, 149.

CHAPTER XII.

Surveying by Instrumental Observation-General Observations-Practical Value

and Simplicity of the Elements of Plane Trigonometry, 153. Trigonometrical Signs,

154. Application of Trigonometrical Tables, 156. Resolution of Plane Right-angled

Triangles, 158. Practical Application of Plane Trigonometry, 161. Resolution

of Oblique-angled Triangles, 163. Abstract or Short Rules, 169. Practical

Observations on the Setting Out of Surveys by Instrumental Observation, 170.

Bases, 172. Practical Examples, 174. Triangulation and Selection of Base,

177—Advantages of the System, 178. Triangulation Station Poles, 179.

CHAPTER XIII.

HYDROGRAPHIC AND HYDRAULIC SURVEYING.

Harbour and Marine Surveying-Preliminary Observations, 181.

Preliminary In-

formation to be Obtained, 183. Outline of Coast, 185. Starring Out, 186.

Buoys, 187.
Station Pointer, 188. Stations, 189. Stations in the Offing, 190.

Buoying out Harbour, 191. Instrumental Observations off the Coast, 193.

Soundings-The Hand-lead, 194. The Plunger, 195. Trying Surface of Har-

bour Bottom-The Diver, 196. Holding-ground-Anchorage, 197. Reducing

Soundings, 198. Tidal Observations-The Tides, 199. The Tidal Wave, 205.

Tides of the Irish Seas, 213. Tides of the Irish Seas and British Channels, 217.

North Sea and British Channel, 219. The Bristol Channel, 223. Mean Tide

Level-Tides of the Indian Ocean, 224. Tide Gauges, 227.

Gathering Grounds for Water Supply-General Observations with Regard to the

Required Survey, 229. Rainfall, 231. The Rain Gauge, 236. The Gauge-

Glass, 237. Position of Rain Gauges, 239. Effects of the Geological Strata, 240.

Discharge from large Districts, Rivers, and Streams, 242. Gauging Streams—

Elementary Theory and Theoretical Discharge, 245. Contracted Vein—Overfall

Weirs-Coefficients of Discharge, 247. Example and Observations on the Value of

Coefficients, 250. Remarks on Experiments, 253. Variations in the Coefficients-

Initial Velocity, 254. Construction and Setting up of an Overfall Weir, 256.

Surface and Mean Velocities, 258. The Current Meter, 261. Flood and Average

Discharge of Stream, 262. Useful Memoranda, 263.

CHAPTER XV.

Levelling. Curvature, 265. The Dumpy Level, 266. Adjustments, 267. Use of the

Level, 270. Levelling Staves, 271. The Practice of Levelling, 273. Backsight

and Foresight; Rise and Fall, 274. Casting out and Reducing, 276. Datum, 277.

Plotting the Section, 278. Intermediate Sights, 279. Bench Marks, 280. Staff-

holder and Levelling Staff, 281. Chaining and Setting Out, 284. Long Sights

and Short Sights, 285. Levelling through Townlands, 288. Retrograde Levels,

Cross Sections, 290. Check Levelling, 291. Trial and Explore Levels, 292.

Working Section, 294. Setting Out Levels, 295. Setting Out Gradients, 296.

Remarks on Levels of Contract Section, 298. Contour Levelling, 302. Improved

Dumpy Level, 304.

289.

APPENDIX.

The Transit Instrument, 305. Copying and Reducing Plans, 306.

The Pentagraph

and Eidograph, 307. The Planimeter and Computation of Areas, 308. Constants

for the use of the Planimeter, 309.

Tables, 310.