CONTENTS.

CHAPTER I.
	PAGE
Introduction:—Historical Sketch—Classification of the Subject—Purposes and Qualities of Instruments—Workmanship—Metals—Aluminium—Framing—Tools—Axes of Instruments—Soldering—Finishing—Bronzing—Lacquering—Graduating —Engraving—Style—Glass-Work—Woodwork—Lubrication—Preservation of Instruments—Packing	[1]
CHAPTER II.
The Telescope as a Part of a Surveying Instrument:—General Description—Qualities—Optical Principles—Refraction of Glass—Limit of Refraction—Reflection—Prisms—Lenses, Convex and Concave—Aberration—Formation of Images—Dispersion—Achromatism—Curvature of Lenses—Telescopes—Eye-pieces—Powers—Dynameter—Construction of the Telescope—Diaphragm—Webs—Lines—Points—Parallax—Examination and Adjustment	[24]
CHAPTER III.
The Magnetic Compass as a Part of a Surveying Instrument or Separately:—Broad and Edge-bar Needles—Manufacture of the Needle—Magnetisation—Suspension—Dip and Adjustment—Lifting—Inclination—Declination—Variation—Correction— Compass-Boxes—Description of Compasses—Ring Compasses—Trough Compasses—Prismatic Compasses—Stand—Surveying with Compass—Pocket Compasses	[59]

CHAPTER IV.
Levels:—Methods of Ascertaining—Level Tubes—Manufacture—Curvature—Sensitiveness—Testing—Reading—Circular Levels—Surveyors' Levels—Y-Levels—Parallel Plates—Adjustments of Y-Levels—Suggested Improvements—Dumpy Levels—Tripod Stands—Adjustment of Dumpy—Collimator—Improvements in Dumpy Levels—Tribrach Head—Diaphragms—Cushing's Levels—Cooke's Levels—Cheap Forms of Level—Hand Levels—Reflecting Levels—Water Levels	[85]
CHAPTER V.
Levelling Staves:—Construction—Various Readings Discussed—Sopwith's—Field's—Strange's—Stanley's New Metrical— Simple Construction—Mining Staff—Papering Levelling Staves—Preservation—Packing Pads—Staff Plate—Staff Level— Practice of Levelling—Index of Bubble—Lamp—Curvature Corrections—Station Pegs—Refinement of Levelling—Levelling Books	[148]
CHAPTER VI.
Division of the Circle and Methods Employed in Taking Angles:—Dividing Engine—Surfaces for Graduation—Vernier—Various Sections—Reading Microscopes—Shades—Micrometers—Clamp and Tangent Motions—of Limbs— of Axes—Use and Wear—Difference of Hypotenuse and Base	[175]
CHAPTER VII.
Theodolites:—Constructive Details of 5-inch and 6-inch Transits—Special Additional Parts—Old Form with Four Screws—Improved Form—Additional Parts—Plummets—Striding Level—Lamp—Adjustments over a Point—Solar Attachment—Photographic Attachment	[214]
CHAPTER VIII.
Specialties in Modern Forms of Transit:—Theodolites for General Surveying—Railway Work—Exploring	[246]

CHAPTER IX.
Plain Theodolites in which the Transit Principle is not Employed:—The Plain Theodolite—Improved Construction—Everest's Simple—Adjustments and Examination of Theodolites	[267]
CHAPTER X.
Large Theodolites used only for Geodetic Surveys:—Stanley's 10- and 12-inch—14-inch Altazimuth—Col. Strange's 36-inch Theodolite	[293]
CHAPTER XI.
Mining Survey Instruments:—Circumferentors—Plain Miner's Dial—Sights—Tripod Stand—Adjustments—Henderson's Dial—Lean's Dial—Adjustments— Hedley's Dials—Additional Telescope—Improved Hedley—Tribrach and Ball Adjustment—Reflectors—Continental Forms—Théodolite Souterrain— Tripod Tables—Stanley's Mining Theodolite—Pastorelli's and Hoffmann's Adjustable Tripod Heads—Mining Transit Theodolites—Stanley's Prismatic Mining Compass—Hanging Dial—Hanging Clinometer—Semi-circumferentor—Mining Lamps	[307]
CHAPTER XII.
Instruments to Measure Subtense or Tangential Angles to Ascertain Distances:—Historical Notes of the Method—Principles Involved—Stadia Measurements, Direct and by the Ordinary Telescope—Corrections for Refraction of the Object Glass—Stanley's Subtense Diaphragm—Anallatic Telescope of Porro—Tacheometers—Stadia—Omnimeter—Field book—Bakewell's Subtense Arrangement	[355]
CHAPTER XIII.
Instruments Constructed Especially for Facility of Taking Inclinations:—Inclinometer Theodolite—Gradiometer—Clinometers: Abney's—Troughton's—De Lisle's—Stanley's—Barker's—Burnier's—Watkin's—Clinometer Sights—Rule Clinometer—Road Tracer	[389]

CHAPTER XIV.
Instruments of Reflection:—Octant or Quadrant—Reflecting Circle—Sextant—Principle—Parallax— Construction—Examination—Adjustment—Artificial Horizon—Sounding Sextant—Box-Sextant—Supplementary Arc—Improvements upon this—Optical Square—Optical Cross—Apomecometer	[422]
CHAPTER XV.
Graphic Surveying Instruments and Appliances Connected therewith:—Plane Tables—Alidades—Telescopic Arrangements—Subtense Measurements—Various Devices for Holding the Paper—Continuous Papers—Adjustment of Tripod Heads—Method of Using—Edgeworth's Stadiometer—Sketching Protractor—Sketching Case—Camera Lucida, etc.	[472]
CHAPTER XVI.
Instruments for Measuring Land and Civil Works Directly:—Chains—Various Tellers—Standard Chains—Arrows—Drop Arrows—Vice for Adjusting Chain—Caink's Rule for Inclines—Steel Bands—Wire Land Measures—Linen Tapes—Offset Rods—Pine Standard Rods—Rods with Iron Core—Beam Compass Rods—Coincidence Measurements—Compensated Rods—Base Line Apparatus—Coast Survey Lines—Perambulator—Pedometer—Passometer—Sounding Chains—Sounding Lines—Telemeters—Hand Rods—Rules	[490]
CHAPTER XVII.
Stations of Observation:—Pickets—False Picket—Permanent Stations—Referring Object—Heliotrope—Heliostat—Heliograph Signalling—Morse Alphabet—Night Lights—Oil Lanterns—Magnesium Light	[533]
CHAPTER XVIII.
Measurement of Altitudes by Differences of Atmospheric Pressure:—Historical Note—Mercurial Barometer—Construction—Operation—Aneroid Barometer—Construction—Various Improvements—Hypsometer	[548]

CHAPTER XIX.
Miscellaneous Surveyors' and Engineers' Instruments, Appliances, and Accessories:—Cross Staff—Mechanics' Levels—Boning Rods—Footner's Railway Gauge—Girth Strap for Timber Measurement—Girth Tapes—Timber Marker—Slashing Knife—Bill-Hook—Reconnoitring Glass—Telescope—Sun Spectacles—Whistles—Pioneer Tools—Sketch Block Book—Camera—Geological Tools—Wealemefna—Opisometer—Boucher's Calculator—Slide Rules—Fuller's Calculator—Engineers' Pocket-Books—Chronometer—Outfits	[573]
Index	[601]

SURVEYING INSTRUMENTS.