A Text-book of Ore and Stone Mining ... With frontispiece and 716 illustrations

Front matter

A TEXT-BOOK OP OEE AND STONE MINING. Stanc-arc- Morfcs FOE THE TSE OF MANAGERS OF MINES & COLLIERIES, MINING ENGINEERS, SURVEYORS, AND METALLURGISTS. PRACTICAL GEOLOGY (AIDS IN). By G. A. J. Cole, F.G.S., Prof. of Geology, Royal College of Science, Dublin. With numerous Illustrations. Second Edition. 10s. 6d. COAL MINING. By H. W. Hughes, F.G.S., Assoc. R.S.M. With 490 Illustrations. Second Edition. 18s. MINE SURVEYING. By B. H. Brough, F.G.S., formerly Instructor of Mine Surveying, Royal School of Mines. Fourth Edition, Illustrated, 7s. 6d. TRAVERSE TABLES ; computed to Four Places Decimals for every Minute of Angle up to 100 of Distance. By Richard Lloyd Gubden, Authorised Surveyor for the Government ot" New South Wales and Victoria. Thibd Edition. 21s. BLASTING AND THE USE OF EXPLOSIVES.

By 0. Guttmaxx, A.M. Inst. CE. With folding Plates and Illustrations. 10s. 6d. ASSAYING. By J. J. Beringer, F.C.S., F.I.C., and C. Beringer, F.C.S. Second Edition. 10s. 6d. ELEMENTS OF METALLURGY ; The Art of Extracting Metals from, their Ores. By J. Abthu___ Phillips, C.E., F.C.S., F.G.S., aud H. Bauebman,. F.G.S. With numerou^-illufttrationsv Third Edition. 36s. NEW METALLURGICAL SERIES E-DsTED BY W. C. ROBERTS-AUSTEN, C.B., F.R.S., Chemist and Assayer of the Royal Mint ; Prof. of Metallurgy f Royal College of Science „ 1.

Introduction

TO THE STUDY OF METALLURGY. By the Editor. Third Edition. 12s. 6d. 2. GOLD. By T. K. Rose, Assoc. B.S.M., B.Sc, Assistant-Assayer of the Royal Mint. 21s. 3. COPPER. By Thos. Gibb, Assoc. R.S.M., F.I.C. 4. IRON AND STEEL. By Thos. Turner, Assoc. R.S.M., F.I.C. 5. METALLURGICAL MACHINERY. By H. Jenkins, Wh.Sc, Assoc. R.S.M., Assoc.M.lnsl.C.E., of the Royal Mint. 6. ALLOYS. By the Editor. *** Other Volumes in Preparation. London : CHARLES GRIFFIN & CO., Ltd., Exeter Street, Strand.. J.C.Burr-ow.PhœtQ. Diz»»onaPk.Ss. ( '/<■/•//////// 'my//- /// ////■ ?/1!r////Afl///j warn Srua , "'/// . ////// 'f ■/>/-//// a//' A TEXT-BOOK OF ORE AND STONE MINING. BY C. LE NEVE FOSTER, B.A., D.Sc, F.R.S., associate of the royal school of mines, one of her majesty's inspectors of mines, and professor of mining at the royal college of science, london, with which is incorporated THE ROYAL SCHOOL OF MINES. WITH FRONTISPIECE AND 716 ILLUSTRATIONS. LONDON: CHARLES GRIFFIN & COMPANY, LIMITED, EXETER STREET, STRAND. 1894. [All rights reserved.]

Preface

. The object of my text-book is to assist students in acquiring a knowledge of the art of mining. Books and lectures are not intended to take the place of practical teaching at mines ; but they render the training more thorough and complete in many ways : they serve to explain the principles of the art, to solve difficulties which perplex the beginner, to suggest matters which he should observe, to tell him of things beyond his ken, and to supply him with a system for arranging his ideas methodically. It will be seen by my numerous references that I have not hesitated to avail myself of very varied sources of informa tion, and that I have taken care to avoid dwelling too much upon English examples. As far as possible I have set my face against the indis criminate use of the local slang of any particular district.

Mining is quite difficult enough without introducing unnecessary technical terms, and if words which are generally under stood by English-speaking nations will express our ideas clearly, it is far better to employ them than to fall back upon provincialisms which vary from one district to another ; on the other hand, certain expressions may sometimes recommend themselves by reason of their pithiness, for adoption into our tongue. Within the limits of this preface it is impossible to name

PREFACE.

. VI all the persons to whom I am indebted for matter contained in this volume. Many useful facts have been picked up while visiting mines at home and abroad, and in the course of conversation with my colleagues. I therefore gladly record my obligations to mining men generally, whom I have invariably found ready to give me the benefit of their experience. I have to thank the Council of the Institution of Civil Engineers, the Council of the Institution of Mechanical Engineers, the Editors of Engineering aud of the Engineering and Mining Journal, M. Paulin Arrault, Mr. Augustus Bowie, Mr. William Galloway, Messrs. Letcher and Michell, and others, for permission to reproduce some of their figures. A few of the blocks have been borrowed from Mr. Hughes' " Text-book of Coal Mining." Mr. J. G. Lawn and Mr. L. H. Cooke have given me valuable assistance in correcting proofs, and the former espe cially has saved me from some of the pitfalls which beset the path of an author who is passing a book through the press.

The very full index prepared for me by Mr. S. W. Price will facilitate reference to my pages. Llakdudno, Noeth Wales, Maij, 1894. GENERAL CONTENTS. Introduction. Chapter I. — Mode of Occurrence of Minerals. PAGE Classification .... 3 Tabular Deposits ... 5 I. Beds .... 5 2. Veins or Lodes . . 5 Masses 18 Examples . ■ • .20 Alum 20 Amber . . ■ • 21 Antimony . . . .21 Arsenic . • • .21 Asbestos . . • .21 Asphalt .... 22 Barytes . ■ ■ -23 Borax .... 23 Boric Acid . . .25 Carbonic Acid . . . 25 Clay 26 Cobalt ore . . . .27 Copper ore - • .28 Diamonds . . . -37 Flint 39 Freestone . . ■ - 41 TAGE Gold ore . . . .41 Graphite . . . -5° Gypsum . . ■ -5° Ice 51 Iron ore . • • 51 Lead ore ... . 55 Manganese ore . . -57 Mica 5^ Natural Gas . . -59 Nitrate of Soda . . .62 Ozokerite . . • • 63 Petroleum . . . -65 Phosphate of Lime . . 67 Potassium Salts . . 69 Quicksilver ore . . • 71 Salt 75 Silver ore . . • -77 Slate 79 Sulphur . • • ■ 81 Tin ore . . • -83 Zinc ore . . • -85 Faults 87 Chapter II.— Prospecting.

Sheading . • • • IOS Hushing . • • • IO° Piercing . • • .106 Lode Lights. - • • i°7 Altered Vegetation . .107 Old Workings . . ■ 108 Names of Places . - .no Divining Rod . . .111 Dipping Needle . . . I II Chance Discoveries . . -93 Adventitious Finds . ■ -95 Geology as a Guide to Minerals 97 Associated Minerals . . ' • 97 Surface Indications . . -97 Form of the ground . - 98 Colour 99 Gozzan 99 Indicative Plants . . • i°3 Animals as Indicators . . CONTENTS VIII Chapter III . — Boring. PAGE Iron Rods . . .124 AVooden Rods . .134 III. Boring by Percussion with Rope . .137 American System . 137 Mather and Platt's System . . . 142 PAGE Uses of Bore-holes . . . 113 Methods of Boring Holes . . 113 I. Boring by Rotation . . 113 Auger . . . .113 Diamond Drills . .118 II. Boring by Percussion with Rods . . . 124 Chapter IV. — '.

Breaking Ground. 2. Percussive Drills . 180 IV. Machines for Cutting Grooves . . . 199 1. Mechanical Picks . 199 2. Travelling Rock Drills . . . 201 3. Circular Saws . 202 4. Endless Chains with Cutters . 204 5. AVire Saw . . 204 6. Revolving Bar with Cutters . . 206 Ar. Machines for tunnelling 206 Modes of using Holes for Breaking Ground . . . 207 Driving and Sinking . . 221 Fire-setting .... 225 Excavating by AVater . . 226 Hand tools . . . .151 Shovel 151 Crowbar . . . -151 Pick 152 Wedge 154 Saws 154 Tools for Boring and Blasting 154 Machinery for Breaking Ground 162 Transmission of Power . . 163 By Air 164 AA'ater . . .171 Electricity . . .172 Excavating Machinery . . 173 I. Steam Diggers . . 173 II. Dredges . . 175 III. Rock Drills . .177 I. Rotary Drills . 177 Chapter V. — Supporting Excavations.

Timbering .... 227 Kinds of Timber used . . 227 Preservation of Timber . 229 Levels ..... 232 Shafts . . . . . 236 Working-places . . . 244 Masonry 249 Levels 250 Shafts 252 AVorking Places . . . 254 Metallic Supports . . . 255 Levels 255 Shafts 263 Working Places . . . 265 Watertight Linings for Shafts 266 Special Processes . . .271 Boring Method . . .271 Compressed Air Method . 277 Freezing Method . . . 279 Haase Process . . . 283 Chapter VI. — Exploitation. Open AVorks .... 285 Hydraulic Mining. . . 292 Excavation of Minerals under Water .... 302 Extraction of Minerals by AArells and Bore-holes . . . 304 Underground AVorkings . . 30S Beds 309 A. Pillar AVorkings . . 309 B. Longwall AVorkings . . 322 A'eins .... 325 Masses CONTENTS. IX Chapter VII. — '. Haulage or Transport. PAGE Underground .... 348 By Shoots .... 348 Pipes . . . .349 Persons .... 349 Sledges .... 350 Vehicles . . . . 350 Wheelbarrow . . 350 Carts and AVaggons . 350 Railways . . . 351 Power Used . . 361 Human Labour . . 361 Animal Labour . . 361 Gravity . . . 362 TAGE Machinery. . . 363 a. Locomotives . 363 b. Stationary Engines . . 364 Conveyance by Boats . . 372 Above Ground .... 373 Shoots 373 Pipes 373 Persons 375 Sledges 375 Vehicles . . . .375 Boats 380 Aerial Ropeways . . . 380 Chapter VIII. — '. •Hoisting or Winding.

Motors, Drums and Pulley Frames .... 387 Ropes, Chains, and Attachments . . . . 398 Receptacles .... 404 (a) Buckets . . . 404 (b) Guided Buckets . . 408 (c) Cage . . . .417 Other Appliances . . . 418 Keps 419 Signals 420 Safety Appliances . . . 422 Overwinding. . . . 422 Stopping Gear . . . 424 Safety Catches . . . 426 Springs 427 Testing Ropes . . . 427 Pneumatic Hoisting . . 427 Chapter IX. — Drainage. Accessories . . . 457 Pumping Engines below ground 466 Worked by Steam . . 466 Water . . 469 Compressed Air . . 470 Electricity . 470 Co-operative Pamping . . 473 Surface AVater .... 429 Dams 430 Drainage Tunnels . . . 433 Siphons 437 Winding Machinery. . . 437 Pumping Engines above ground 441 Motors .... 442 Rods 445 Pumps .... 447 Chapter X. Ventilation. Atmosphere of Mines . . 475 Causes of Pollution of Air in Mines .... 480 Natural Ventilation . . . 482 Artificial Ventilation . . 490 I. Furnace Ventilation . 490 II.

Mechanical Ventilation . 491 Water Blast . .491 Steam Jet . . . 492 Air Pumps (Fans) . 492 Testing the Quality of Air . 498 Fire Damp .... 498 Carbonic Acid . . . 501 Oxygen . . . .505 Measuring the Quantity and Pressure of the Air . . 506 Anemometers . . 507 Water Gauge . . . 50S Efficiency of Ventilating Appliances 509 Resistance caused by Friction . CONTENTS. X Chapter XL— Lighting. PAGE Reflected Daylight . . .513 Candles 513 Torches 515 Lamps 515 PAGE AVells Light . . • • 5 "6 Safety Lamps . . • • 5l8 Gas . - - ' • • -523 Electric Light . . . • 523 Chapter XII. — Descent and Ascent. Steps and Slides . . . 526 Ladders 527 Buckets and Cages . . ■ 531 Man Engine .... 534 CnAPTER XIII Dressing. Buddies . . 587 Motion in Air . . 589 Desiccation .... 592 Liquefaction and Distillation . 597 Magnetic Attraction . . 600 III.

Processes depending upon Chemical Properties . 607 Solution, Evaporation, and Crystallisation . 607 Atmospheric Weathering .... 610 Calcination or Roasting 611 Cementation . . . 616 Amalgamation . . 616 Application of Processes . . 620 Loss in Dressing . . . 630 Sampling .... 632 Hand Sampling . . 632 Machine Sampling . . 634 I. Mechanical Processes . 538 Washing . . . 538 Hand Picking . • 541 Breaking Up . . 542 Agglomeration or Consolidation . . . 5^5 Screening . . . 566 II. Processes depending upon Physical Properties . 568 Motion in AVater . . 568 Simple Fall in Water . 570 Upward Current Separators . . 574 Separation by Water Flowing down Planes . . . 579 Plane Tables . 579 Percussion Tables 584 Travelling Belts . 585 Chapter XIV. — Principles of Employment of Mining Labour, Payment by Time . . . 637 Payment by Combination of these64i Measure or Weight 63S Value of Product . 641 Chapter XV. — Legislation Affecting Mines and Quarries.

Ownership .... 653 Taxation ..... 655 Working Regulations . . 655 Metalliferous Mines Regulation Acts .... 656 Coal Mines Regulation Act . 662 Other Statutes affecting Mines 662 Alkali Acts .... 665 Boiler Explosions Acts . . 666 Brine Pumping Act . . 666 Elementary Education Acts . 666 Employers' Liability Act . 666 Explosives Act . . . 666 Factory and Workshop Acts 667 Quarry F'encing Act . . 667 Rivers Pollution Prevention Act 667 Stannaries Act . . . 668 Truck Acts .... 66S CONTENTS. XI Chapter XVI. — Condition of the Miner. PAGE Clothing 669 Hat 671 Boots 672 Jacket 673 Housing ..... 673 Barracks .... 674 PAGE Cottages .... 677 Education .... 682 Sickness ..... 683 Thrift 690 Recreation .... 696 Chapter XVII. — Accidents. Death Rate of Miners from Accidents .... 698 Relative Accident Mortality Underground and Aboveground 699 Classification of Accidents . 702 Underground . . . 704 Explosions of Fire Damp or Coal Dust . . . 704 Falls of Ground . . 704 Shaft Accidents . . 705 Miscellaneous . . . 706 On the Surface . . . 711 By Machinery . . 711 Boiler Explosions . . 711 Miscellaneous . . 711 Ambulance Training . .712 ERRATA ET CORRIGENDA.

Page 36, line 10 from bottom, for " Kearsage " read "Kearsarge." „ 36, „ iS „ „ "33,359,ooo" „ "33.350,000. „ 124, „ 17 „ ,, "Healey" „ "Beal." „ 182, „ 10 „ „ "Githen" „ "Githens." „ 209, „ 17 „ „ "Nobel" „ "Noble." 3ii. „ 4 from top " detachod " ,, "detached." „ 607, „ 16 „ „ "Buttengenbach" „ " Biittgenbach.' 11 675, owing to an error in the original, the scale is incorrect, and the readings should be multiplied by Frontispiece : Overhand Stoping, Carn Brea Tin Mine, Cornwall. OCCURRENCE. FIG. PACE I. Stratified deposits, section 5 2. Lead lode in slate, Wheal Mary Ann, Menheniot, Cornwall . 6 3. Tin lode in granite, West Wheal Basset, Cornwall ... 7 4. Section of lode, Canton mine, Otago, New Zealand ... 8 5. Diagram to show underlie ........ 10 6. Measurement of underlie 10 7. General section of a lode . . . . . . . .10 8.

Longitudinal section of a lode showing ore-bodies . . .11 9. Intersection of veins . . . . . . . . .12 10. Section of vein with feeders 12 11. Plan showing fahlbands, Kongsberg silver mines, Norway . . 12 12. Change of strike affectiDg richness of a lode .... 13 13. Richness or poverty of parallel parts of lodes : " Ore against ore " 17 14. Hæmatite deposit, Ulverston .... ... 19 15. Calamine deposit, Altenberg, Moresnet ..... 19 16. Stockwork, Mulberry mine, near Bodmin, Cornwall ... 19 17. Borax Lake, California, plan 24 18. Cobalt ore, Skutterud, Norway 27 19. ,, „ New Caledonia 28 20. Section across Mansfeld district ....... 28 21. „ of Eduard II. Shaft, Mansfeld 30 22. Geological map of Rio Tinto, Huelva, Spain . . . 31 23] [• Cross-sections of South Lode, Rio Tinto 32 26 J zl [ Cross-sections of San Dionisio Lode, Rio Tinto .... 33 29.

Map of Lake Superior copper district 35 30. De Beers mine, Kimberley, vertical section .... 38 31. Plan of diamond-bearing deposits, Kimberley .... 38 32. Section of strata at the flint mines, Brandon, Suffolk . . 40 33. „ „ Salisbury mine, Johannesburg ... 42 34. „ Sheba mine, Barberton ...... 43 35. „ auriferous alluvium, Caratal District, Venezuela. . 44 36. „ showing auriferous " rainwash," Caratal ... 45 ll [ Saddle-reefs, Bendigo 46, 47 3s; LIST OF ILLUSTRATIONS. FIG. PAGE 39. Mount Morgan mine, Queensland, section to illustrate geyser theory ....•• 4* 40. „ „ ,, view of deposit 49 41. ,, ._ sections based on late developments ... 50 42. Gypsum mine, Nottinghamshire . . . . . • ■ 51 43. Sections of ironstone bed, Cleveland ....-• 52 44. Chapin Iron mine, Lake Superior, section 54 45.

Lead-bearing sandstone, Mechernich, general section . . 55 46. Evening Star mine, Leadville, Colorado, section . . . 56 47. Manganese ore bed, near Barmouth, North AVales ... 58 48. Natural gas ; section through Findlay, Ohio .... 60 49. Nickel deposit, New Caledonia 60 5° I „ bearing veins, New Caledonia 61 52l „ deposit, Sudbury, Canada 61,62 54. Nitrate of soda, Chili • .62 55. Ozokerite at Boryslaw, Galicia, plan 63 56. ,, „ „ section ..... 64 57. „ filling fissures, Boryslaw ...... 64 5S. Baku oil region, section 65 59. Spouting oil well, Baku ........ 66 60. Deposit of phosphate of lime, Beauval, France .... 68 61. Bed of phosphatic nodules, South Carolina . .... 68 62. Potassium salts and rock salt, Stassfurt ..... 70 63. Quicksilver-bearing sandstone, section, Ekaterinoslav, Southern Russia -72 64.

Cross section of quicksilver deposit, Great Western mine, California 73 65. Longitudinal section ,, „ „ . 74 66. Cross section of Eureka mine, Nevada ..... 77 67. „ „ slate beds, Festiniog, N. Wales .... 80 68. „ „ the Oakeley Quarries, Festiniog .... 81 69. Sulphur bank, Iceland 82 70. „ seam, near Caltagirone, Sicily ..... 82 J} \ Cross sections of tin veins, St. Agnes, Cornwall .... 84 73. Map of part of Vegetable Creek, New South AVales ... 85 74. Cross section showing " deep-leads " of tin ore, Vegetable Creek 86 75. AVash-ont fault 87 76. Ordinary fault 88 77. Step fault 88 78. Fault with zone of broken rock 88 79. Measurement of throw of a fault ...... 89 80. Section of fault indicating amount of throw .... 89 81 1 82 f Variation of throw along the strike of a fault .... 90 83. Reversed fault showing bending of strata 90 84- !■ _ „ 90 85.

Plan showing heave of vein sideways 91 86. Illustration of heave sideways produced by a sliding along dip of fault . . . .91 87. Schmidt and Zimmermann's rule ...... 92 88. Succession of faults, Penhalls mine 92 PROSPECTING. 89. Section of mineral vein showing projecting outcrop of a hard vein FIG. PAGE 90. "Cross-section of lode with gozzan 101 91. Longitudinal section showing relation of the gozzan to natural drainage level 101 92. Use of the divining rod in 93. Dipping needle used in searching for iron ore . . . .112 BORING. 94. Earth auger or gouge 114 95. Derrick for lifting rods 114 96. ,, &c, for boring by rotation . . . . . 115 97. Screwed coupling for hollow boring rods 116 98. Rotating and guiding arrangements and loose connection . . 117 99. Boring bit with two sets of cutters 117 100.

Cutting out a core with diamond drill . . . . .118 101. Plan of large crown for diamond drill 118 102. Arrangement of core tube and sediment tube . . . 119 103. Core-extractor 119 104. Dauntless diamond drill . . . . . . . .120 105. Little Champion diamond drill 123 106. Small diamond drill for prospecting 123 107. Chisel bit 125 108. Screw-joint for boring-rods 125 109. „ „ ,, with connecting socket . . . 125 no. Lis ting hook or dog 125 in. Retaining key 125 112. Cap, or lifting ring and socket 125 113. Portable plant for boring with rods 126 114. Set of tools for use with above 127 115. Shell-pump or sludger 128 1 !- Oeynhausen's sliding joint 129 118 |l>ee-falling tool 129 120. Arrault's free-falliDg tool used with bumping piece . . . 130 121. Enlarged view of catch for free-falling tool . . . .130 122.

Kind's free-falling tool 130 123. Crow's-foot ........... 131 124. Bell-screw 131 125. Riveted lining tube with screwed joints 131 126. Lining tube with flush screwed joint 131 I2Z I Rotating tool for cutting out a core 132 129. Core extractor 132 '3° f Compass-case for marking core 133 131. AVooden boring rod used in Galicia 134 132. Rig for boring by the Canadian system 135 133. American rig for boring a well 138 134. Rope-socket 139 135. Sinker-bar 139 136. Jars 139 137. Auger-stem 139 SI*4 140. Temper screw 140 141. Sand-pump . 140 142. Method of working maul for drive-pipe FIG. PAGE 143. Boring plant, Mather and Platt's system '43 144. Enlarged view of Mather and Platt's cylinder and pulley . . 144 145. Mather and Platt, boring head and turning device . . .146 146. Recording phial for Macgeorge's clinograph .... 147 I4l \ Survey of bore-hole, Scotchman's United mine, Victoria . . 149 BREAKING GROUND. 149.

Poll-pick 152 150. Double-pointed pick 152 151. Pick used for cutting jail, Bath stone quarries . . . .152 152. ,, with movable blade, Mansfeld 152 153. Acme pick • l53 154. Universal pick XS3 155. Cornish gad .......... 154 156. Saw for cutting freestone 154 157. Elliott drill 155 158. Ratchet drill 155 159. Jumper used at Mechernich 156 160. „ ,. in Northamptonshire 156 161. „ in Festiniog slate mines ..... 156 !62. ,, 1, in Cleveland iron mines . ..... 156 163. Borer or drill 156 x54 1 Cutting edge of drill, Minera, North AVales . . . .158 165) 166. Bore-hole with triangular section 159 167. Hammer for single-handed boring, Festiniog .... 159 168. Cornish mallet, or double-handed boring hammer . . . 160 169. Tamping bar 160 170. Needle, or pricker . 161 171. Charging spoon and scraper 161 172.

Claying bar 161 1 73 ' Knox system of boring rending holes 162 T74) 175. Reamer, or broach for enlarging holes by the Knox system . 162 176. Hanarte air-compressor . 165 177. Dubois and Francois air-compressor 166 178. Ingersoll-Sergeant air-compressor 167 179. Valve of Ingersoll-Sergeant air-compressor .... 168 180. Arrangement of steam and air cylinders ..... 168 181. Underground reservoir for compressed air, Mansfeld . . 169 182. Joint for compressed air main, Blanzy . . . . .170 „3 - Mode of fixing air main in shaft 170 184) 185. Eadie and Sons' joint for lap-welded pipe ..... 170 186. Dunbar and Ruston's steam navvy ...... 174 187. Kincaid and McQueen's bucket dredge ..... 176 188. Priestman's grab dredger 177 189. Steavenson's twist drill on carriage, worked by electric motor . 179 190. ,, „ „ „ petroleum engine 180 191] J92 L Bits used with machine drills 1S1 I93[ 194) 195.

Shaped bars of steel for cross-bits 182 196. Barrow drill 187 197. Drill mounted on stretcher bar 1S4 FIG. PAGE 198. Climax drill 185 199 - Bosseveuse, or boring ram of D-abois and Francois . . .186 200 j J ° 201. Ingersoll-Sergeant Eclipse drill 188 2°2} Socket for holding the tool 189 204. Franke drill 19° 205. Use of Franke drill and undercutting chisel, Mansfeld copper mines .......■•■■ '91 206. Hirnant drill 192 207. Sergeant drill 193 208. ,, turning mechanism 194 209. Adelaide drill T95 210. Darlington drill, longitudinal section 196 211. „ „ side elevation 196 212. „ „ mounted on stretcher-bar .... 197 213. Marvin electric drill, working parts 198 214. Franke's mechanical chisel ........ 200 215. Gillott and Copley's undercutting machine 203 216. Walker's circular saw 204 217. Wire saw 205 218.

Stanley's tunnelling machine, side elevation .... 207 219. Elliott multiple wedge, longitudinal and cross sections . . 208 220^ 221 222 L Strength of explosives as shown by Trauzl's lead block test . 216 224 225 226. Detonator, Nobel's, treble strength 218 227. „ „ quintuple strength 218 228. Firing a charged hole ....••••• 219 229. Rifting hole with air-space above charge, Knox system . . 219 230. Simultaneous fuse of Bickford, Smith & Co 219 231. Brain's high-tension electric fuse 220 232. Nobel's „ „ ,, „ 221 233. „ low-tension „ „ 221 234. Planning holes for driviDg a level by hand 222 235. Section of lode with govge or selvage 222 236. Arrangement of holes for driving a level with a machine drill (elevation) . ■ 223 237. Arrangement of holes for driving a level with a machine drill (longitudinal section) 223 238.

Halkyn drainage tunnel, arrangement of holes for driving . 223 239. Driving level with Ferroux drill and bosseyeuse, Bex, Switzerland 224 240. Arrangement of holes for sinking a shaft, Foxdale, plan . . 225 tit t » section . 225 241. ,, ,j jj a j SUPPORTING EXCAVATIONS. 242. Level with cap or bar supporting roof 232 243- » .- - and leg 232 244 1 Joints between cap and leg 232 245 J 246. Timber frame and lagging for level 232 247. Horned set for level in loose ground . . . . - -233 248. Timber frame and lagging for heavy ground, Comstock lode . 233 249. Timbering for level, Rio Tinto mines ■ 233. FIG. PACE 250. Pigsty timbering for wide level, cross-section . . _ ■ • 234 251. „ „ ,, „ section along line of strike . 235 252. Spilling in loose ground, longitudinal section . 236 253. ,, „ „ cross section 236 254.

Plank lining for shaft, plan 237 255. Shaft frame or set 237 256. „ ,, enlarged view of joint ....•• 237 257. Plan of timbering for shaft, Comstock lode .... 238 258. Section through dividing ,, „ .... 23s 259. End view of timbering for shaft ,, ,, .... 238 260. Plan of timbering for shaft, Calumet and Hecla mine . . 239 261. Shaft timbering, Clausthal, plan 240 262. ,, ,, ,, end view ...... 241 263. Timbering chamber for water-wheel, Clausthal .... 241 264. Plan of shaft frame for spilling ....... 242 265. Sinking shaft by spilling, vertical section 243 266. Prop supporting roof of bed ....-■• 244 267. Chocks supporting roof ....•••• 245 26S. Large chocks, AVieliczka salt mines . . . ■ • 245 269. Pigsty timbering in stopes, Day Dawn mine, Queensland . . 245 270. Square set, Comstock lode, Nevada, elevation .... 246 271. „ „ „ ,, plan 246 272. ,, ,, „ ., application in overhand stopes 246 273. „ Richmond mine, Nevada ...... 247 274. „ timbering in overhand stopes, Broken Hill mines, sectional elevation. ...... 248 275. ,, timbering in overhand stopes, Broken Hill mines, horizontal section ...... 248 ■ 276.

Joint for square set, Broken Hill mines . . . . 249 277. Square sets supporting hanging wall ...... 249 278. Strengthening square sets ........ 249 279. Dry walling for level, Forest of Dean ...... 250 280. Le . el lined with masonry, Clausthal ...... 250 281. Level with arch of masonry 251 282. ,, „ „ at side ........ 251 283. Lining shaft with brickwork ....... 252 284. Shaft lined with concrete, Foxdale mine 253 285. Stone pillar supporting roof ....... 254 286. Halkyn drainage tunnel, section showing iron supports . . 255 287. „ „ „ cast-iron prop and chair . . . 255 288. „ ,, ,, section of iron rail used . . . 256 289. Section of steel beam, Nunnery Colliery, Sheffield . . . 256 290. Steel beam on timber legs ........ 257 291. Rolled steel caps and legs forming frame for level . . . 258 292 I Section and plan of steel plate used 258 294.

Level lined with curved iron rails. Hartz 258 295. Bent steel bar for supporting roof of level ..... 259 296. Steel frame in two parts for lining level, Anzin .... 259 297. Cross section showing joint ....... 260 29S. Steel frame in three pieces, Anzin ...... 260 299. Circular frame for level, channel steel ..... 261 300. Section through joint of the frame ...... 261 301. Circular frame for level, bulb-tee steel ..... 262 302. Section through joint of the frame ...... 262 303. Iron ring in two parts for supporting shaft lining . . 26- 304. Shaft, lining, ozokerite mines, Boryslaw ..... 264 305. Ring of channel iron for shaft ...... 264 306. Section through joint of ring 26; FIG. PAGE 307. Prop of I-steel, and plan of end ....... 266 308. Solid wooden tubbing for shaft, plan 266 309. Sections of cast-iron wedging cribs ...... 267 310.

Section through coffering 268 311. Segment of castiron tubbing 269 TJ2 ) ~ r Cast-iron tubbing resting on curb ...... 270 314. Small composite borer or trepan, Kind-Chaudron system . . 272 315. Large composite borer „ „ „ . . 273 316. Section of tubbing with moss-box „ „ ,, . . 274 317. „ ., ,, „ compressed, and false tubbing 274 318. Enlarged section of the three wedging curbs .... 274 319. Section of tubbing at Lievin 276 320. Sinking by freezing process in watery strata, Siberia . . . 279 321. » >> » » „ 280 322. Poetsch's freezing process, section of freezing tube . . . 282 323. „ ,, „ vertical section of shaft . . . 282 EXPLOITATION. 324. Open workings for iron ore, Northamptonshire .... 287 325. ,, ,, plan showing arrangement of workings . . 288 326. Section of terraces, Penrhyn slate quarry ..... 288 327.