INDEX.

[ A ][ B ][ C ][ D ][ E ][ F ][ G ][ H ] [ I ][ J ][ K ][ L ][ M ][ N ][ O ][ P ] [ R ][ S ][ T ][ U ][ V ][ W ][ Y ][ Z ]

[The subjects illustrated in the engravings are indicated by italics, the names of authors are in Capitals.]

ABICH, cited, 122 — researches of, 4 Absorption of gases by liquids and solids, 354, 355 Acid lavas, 48 Æolian Islands. See Lipari Islands Æolus, origin of myth, 35 Africa, volcanoes of, 227 — South, diamonds of, 147 Agates, formation of, 150 Allport, Mr., cited, 259 Alps, formation of, 292 Altered lavas, names given to, 261 America, volcanoes of, 227 Amygdaloids, formation of, 140, 141 Andesites, 50, 59 Andesite-volcanoes, 126 Andrews, Professor, cited, 321 Anne Boleyn and Etna, 3 Armstrong, Sir W., hydro-electric machine, 29 Arthur's Seat, 275 Artificial stone, 55 Asia, volcanoes of, 227 Asiderites, 316 Asmanite, 314 Astroni, crater-ring of, 170 Atlantic, volcanoes in, 223 Auvergne, breached cones of, 123, fig. 40 — denuded cones in, 124, fig. 42 — incrusting springs of, 184 — puys of, 152, 212 — volcanic cones in, 79 BALL-AND-SOCKET structure in basaltic columns, 107 Barrancos, formation of, 209 Basalt, controversy concerning origin of, 249 Basalts, 49, 50, 59 Basaltic columns of Bohemia, 107 — — of Central Germany, 107 — — of Monte Albano, 107 — — from the Giant's Causeway, 107, fig. 29 Basic lavas, 48 Bath, hot spring of, 219 Ben Nevis, 274 Bohemia, volcanoes of, 126 — lavas of, 103 Boiling. See Ebullition Bonney, Professor, cited, 69, 109, 259 Boracic acid at volcanic vents, 216 Bourbon, volcano of, 176, figs. 74, 75 Bracciano, crater-lake of, 178, fig. 77 Breached cones, 123, fig. 40 Babbles of steam, escape from lava, 21 Bubbles, spontaneous movement of, in liquid cavities, 62, fig. 8 — — cause of, 65 Buch, Von, researches of, 4 Buda-Pesth, deep well of, 335, 341 Büdos Hegy, Transylvania, 215 Bunsen, cited, 201 Burning, does not take place at volcanoes, 2 CADER IDRIS, 274 'Calderas,' formation of, 180 Caldera of Palma, 209 Cambro-Silurian volcanoes of British Islands, 274 Campi-Phlegræi, map of, fig. 11 — — volcanoes of, 79 — — tuff-cones of, 118 — — fissures in, 197 Carbonic acid in cavities of crystals, 63 Carboniferous volcanoes of British Islands, 275 Carlsbad, Strudel of, 218 — Strudelstein of, 184 Caspian Sea, mud-volcanoes of, 182 Catacecaumene, volcano cones in, 79 Cause of proximity of volcanoes to sea, 239 Central Asia, volcanoes of, 236 — America, mud-volcanoes, 182 — Pacific, volcanoes of, 236 'Challenger,' H.M.S., voyage of, 73 — — soundings of, 359 Chance, Messrs., of Birmingham, 55 Charnwood Forest, ancient volcanic rocks of, 259 Chemical deposits at Vulcano, 44 — — on surfaces of lavas, 110 — elements present in lavas, 46 — theory of volcanoes, 344, 346 Chiaja di Luna, 108 Chimborazo, size of, 44 — 151 Chodi-Berg, Hungary, 161 Citlaltepetl, view of, 169, fig. 69 Coast-lines, proximity of volcanoes to, 228 Cole, Mr. Grenville, 110 Colours of lavas, 49 Columns in lava, 105 — — dimensions of, 105 — radiating in intrusive masses, 136 Columnar structure in lavas, 104 — — origin of, 105 Columnar lava-stream on the Ardèche, 107, fig. 28 Combustion, does not take place at volcanoes, 2 Composite cones, 128, 161 Comstock mines, temperature of, 342 Concentric jointing in lava, 108, fig. 30 Cones composed of viscid lava, 129, fig. 43 — miniature on lava-streams, 100, 101, figs. 25, 26 — natural sections of, 129 — shifting of axis in, 167 Coolin Hills, Skye, 144 Cotopaxi, volcanic dust of, 69 — view of, 168, fig. 68 Craters, formation of, 82 — origin of, 167 — position of, 167 — fissuring of sides, 180 Crater of Stromboli, aperture at bottom of, 15 Crater-lakes, formation of, 171 — of Agnano, 171 — of Albano, 171 — of Avernus, 171 — of Bagno, 171, fig. 71 — of Bolsena, 171 — of Bracciano, 171 — of Frascati, 173, 175 — of Gustavila, 171, fig. 72 — of Laach, 171 — of Nemi, 171 Crater-rings, formation of, 170 Crater-ring of Somma, 177, fig. 76 Crater-ring of Pianura, 174 — — of Piano di Quarto, 174 — — of Vallariccia, 174 Creuzot, shafts at, 340 'Critical point' of liquids, 63 Crust of globe, definition of, 308 Crystals in lavas, 51 — — formed of crystallites, 54-57 — — formed in subterranean reservoirs, 60 — — interruption in growth of, 60 — pressure under which formed, 65 — deposited on surface of lava, 110 — porphyritic, origin of, 256 Crystalline minerals formed beneath volcanoes, 146, 147 — — ejected from volcanoes, 147 Crystallised minerals of volcanoes, 46 Crystallites, aggregates of, 54, Frontispiece Crystallites in lavas, 53, Frontispiece Crypto-crystalline base, 57 'Cupolas,' 135 Corral of Madeira, 209 DACITES, 198 Dana, Professor, J. D., cited, 100, 159, 291, 301, 327, 338, 339 Darwin, Mr., cited, 245, 246, 271, 289 Daubeny, cited, 182 Daubrée, M., cited, 147, 315, 320, 358 Daubréelite, 314 Davy, Sir Humphry, chemical theory of volcanoes, 344, 345 Deccan of India, 103 Density of the earth, 306 Denuded cones and craters, 158, fig. 59 Denudation, effects of, on volcanoes, 114 Deposits about volcanic fissures, 42 Detonations at Vesuvius, 26 Devonian volcanoes of British Islands, 274 Diorite, 59 Dolomieu, cited, 4, 39 Durocher, cited, 201 Dykes, formation of, 116, 117, 209, 210 — structure of rock in, 211 — pseudo-, 119 Dynamical theory of volcanoes, 347, 348 EARTH'S interior, nature of, 309 — — physical condition of, 325 — — hypothesis concerning, 328-330 — relation to other planets, 310, 311 Earthquakes, depth of origin of, 343, 344 — connection with volcanoes, 343 — accompanying Vesuvian eruption of 1872, 27 Ebullition, compared to volcanic eruptions, 19, 20 Eifel, volcanic cones of, 45 Ejected blocks, 45 — materials, height to which thrown, 72 — — stratification of, 117-119 Elements, pyroxenic and trachytic, theory of, 201 Elevation-craters, theory of, 135, 200 Erroneous opinions, sources of, in regard to volcanoes, 2 Eruptions, feeble and violent compared, 31 — prediction of, not possible, 32 — intervals between, 33 — of varying intensity, 33 — and barometric pressure, 36 — effects of repetition of from same fissure, 80 Eruptive action in sun and moon, 360-369 Etna, ideas of ancients concerning, 3 — and Anne Boleyn, 3 — observatory on, 37 — size of, 44 —, 151 — eruptions at summit and on flanks, 207 Etna, dyke and lava-stream in, 133, fig. 54 Etna, views of, 162, 163, figs. 62, 63 Euganean Hills, 139 — — volcanoes of, 201 Europe, volcanoes of, 227 Extra-terrestrial rocks, 316 Extra-terrestrial rocks, relation to ultra-basic rocks, 322, fig. 88 FELSTONES, 263 Ferric-chloride, mistaken for sulphur, 41 Fissure on flanks of Etna, 194, fig. 84 Fissure-eruptions, 188 Fissures, volcanic cones on, 194 — systems of, 198 Fingal's Cave, 106 Flames, phenomena mistaken for, 2 — at volcanoes, feebly luminous, 17 — false appearance of, in volcanoes, 17 Flames at volcanic vents, 41 Flashing lighthouse, compared to Stromboli, 10 Floods, accompanying volcanic outbursts, 30 Forbes, Mr. David, cited, 337, 339 Fossils, from beneath Vesuvius, 45 — supposed in basalt, 250 Fouqué, M., cited, 110, 213 Fumaroles, gases emitted from, 213 Fusiyama, form of, 90, 166 Fusiyama, 178, fig. 77 GABBRO, 59 Gardiner's river, travertine terraces of, 185 Gases emitted from volcanoes, 40 — — volcanic vents, 212-216 Geanticlinals, formation of, 297 Gems, formation of, 147 — mode of occurrence, 148 Geological continuity, doctrine of, 247 Geosynclinals, formation of, 294 Geysers, formation of, 217 — intermittent action of, 218 — of Colorado, 184, 217 — of Iceland, 184, 217 Giant's Causeway, 108 Gilbert, Mr. G. K., cited, 208 Girgenti, mud-volcanoes of, 182 Glass, formed by fusion of lavas, 52 Glasses, composed of certain silicates, 58 Glassy base, 57 Goethe, cited, 112 Graham Isle, 178, 179, fig. 78 Graham, cited, 345 Grand Sarcoui, Auvergne, 161 Granite, 59 Granite of Secondary and Tertiary ages, 254 Granitic rocks, position beneath volcanoes, 145 Great earth movements, nature of, 286 Great volcanic bands of the globe, 232-234 Grenelle, boring of, 341 Greystones, 49 Groundmass of lavas, 52 Grotto del Cane, 215 Guevo Upas, Java, 215 Guiscardi, Professor, referred to, 45 Gustavila, crater-lake of, 172, fig. 72 HAMILTON, Sir W., researches of, 4, 75, 84 — — observations on Vesuvius, 80 Hannay, Mr., referred to, 147 Hartley, Mr. Noel, referred to, 65 Hawaii, volcanoes of, 100, 125 — — lava-masses of, 159 — — volcanic eruptions at different levels, 327 Hebrides, volcanoes of, 271 Henry, Dr., cited, 355 Henry Mountains, Southern Utah, 208 Hephæstus, forge of, 3 Hochstetter, cited, 135, 356 Holosiderites, 315 Hopkins, Mr., cited, 349 Hot springs, numbers of, 219 Humboldt, researches of, 4 Hungary, lavas of, 96, 103 — volcanoes of, 126, 201 — deep wells of, 341 Hverfjall, Iceland, 178, fig. 77 Hydro-electric machine of Sir W. Armstrong, 29 Hypothesis, value of, 331-333 ICE under lava of Vesuvius in 1872, and of Etna, 110 Iceland, volcanic dust of, carried to Norway, 72 Indian Ocean, volcanoes in, 229 Insel Ferdinandez, 178, 179, fig. 78 Intermediate lavas, 48 Intervals between Eruptions, 33 Ireland, north-east of, 103 Iron in Ovifak-basalts, 319, fig. 87 Iron, seething of, 356 — of Ovifak, terrestrial origin of, 320 Ischia, eruption in 1301, 164 — crater-lake of Bagno in, 172, fig. 71 — plan of, 163, fig. 64 — parasitic cones in, 164, fig. 65 Island of Bourbon, 93 Isle Julie, 178, 179, fig. 78 Isogeotherms, 359 JANSSEN, referred to, 42 Joint-structures in lava, 104-110 KAMMERBÜHL, 112-114, fig. 33 — section of, 114, fig. 34 — section in side of, 118, fig. 36 Kant, nebular hypothesis of, 352 Kilauea, volcano of, 71, 138 — crater of, 181 King, Mr. Clarence, cited, 301 LAACHER SEE, minerals ejected at, 149 Lac Paven, Auvergne, 171, fig. 70 'Laccolites,' formation of, 208 Lago di Bolsena, 173, 175 Lago di Bracciano, dimensions of, 172, 173 Lake Avernus, 215 Lapilli, 70 Laplace, nebular hypothesis of, 325, 352 Lavas, action of acid gases on, 41 — resemblance to slags, 46 — chemical elements in, 46 — oxygen in, 47 — silicon in, 47 — proportion of silica and other oxides in, 47 — silicates in, 47 — acid, intermediate, basic, 48 — specific gravities of, 49 — colours of, 49 — microscopic study of, 50 — fusibility of, 51 — minerals in, 51 — artificially fused, 51 — crystals in, 51, 93 — ground mass of, 52 — crystalline forms of, 59 — of Bohemia, 103 — of Hungary, 96, 103 — of Kilauea, 95 — of Lipari, 96 — of Niedermendig, 103 — of Vesuvius, 104 — of Volvic, 95 — of Volcano, 95 — presence of water In, 102 — chemical deposits on, 110 — different fluidity of, 204 — augite and hornblende in, 267 Lava, cascade of, 93, fig. 18 Lava-cones, composed of liquid lava, 125 — — of viscid lava, 126, 127 — characters of, of liquid lava, 159 — — of viscid lava, 160 Lava-cones, outlines of, 160, fig. 60 Lava, in deep-seated reservoirs, 138 — consolidation of, at great depths, 139 Lava-fountains, 94 Lava-sheets, intrusive, 136, 137, fig. 56 'Lava' ornaments of Naples, 45 'Lava,' slow-cooling of, 110 — a bad conductor of heat, 110 — ice under, 110 Lava-streams, nature of movements, 92 — difference in liquidity of, 92 — miniature cones on, 100, 101 — vast dimensions of, 102 — structure of, 103 — position of columns in, 106 — sinking of surface of, 111 'Lave di fango,' 30 'Lave di fuoco,' 30 Lawrencite, 314 Laws of volcanic action, 38 Le Conte, cited, 347 Leucite, absence from ancient lavas, 268 Lightning, accompanying volcanic outbursts, 28 Linear arrangement of volcanic vents, 191 — — of volcanoes, 231 Lipari Islands, 3, 39 — — fissures in, 197 — — pumice-cones in, 154 — — order of appearance of lavas in, 200 — — breached pumice-cones in, 124, fig. 41 — — map of, 192, fig. 81 — — lavas of, 96, figs. 20, 21 Liquids in cavities of crystals, 63 Liquid cavities in lavas, 60, fig. 7 — — spontaneous movement of bubbles in, 62, fig. 8 — — spontaneous movement of bubbles in, cause of, 65 Lockyer, Mr. Norman, cited, 322, 363, 364 Lunar craters, 368, fig. 95 Lyell, Sir Charles, cited, 135, 167, 197 MACCULLOCH, cited, 207, 208 Madeira, cliff-section in, 128, fig. 47 Magmas, theory of, 201 — objections to, 202, 203 Mallet, Mr., cited, 269, 343, 346 Mamelons of Bourbon, 126, 127, figs. 45, 46 Maskelyne, Professor, cited, 314 Massa di Somma, destruction of, 26 Mauna Loa, 138 Metamorphism around volcanic vents, 145 Meteorites, nature of, 312 — composition of, 313 — minerals of, 314 — classification of, 315 Melaphyres, 262 Miascite, 59 Michel Lévy, M., 110 Micro-crystalline base, 58 Microliths. See Crystallites Microscopic study of lavas, 50 Minerals in lavas, 51 — of Vesuvius, 46 Mineral-veins, formation of, 149 — connection with volcanoes, 220 — nature of materials in, 321 Misenum, Cape of, section of tuff-cone of, 121, fig. 38 Modena, mud-volcanoes of, 182 Mont Dore, section at, 130, fig. 48 Monte Cerboli, Tuscany, 216 Monte Massi, Tuscany, well at, 341 Monte Nuovo, history of formation of, 76 — — description of, 77, 78, fig. 10 — — 152 — — crater of, 168 — — production of fissure at, 190 Monte Rotondo, Tuscany, 216 Moon, effect of internal forces on, 305 Mountains, all volcanoes not, 2 Mountain-chains, formation of, 291 — — all of recent date, 292 Mud-streams at volcanoes, 30 Mud-volcanoes, formation of, 181, 182 Mull, dissected volcano of, 142-4, figs. 57, 58 Muscovite, absence of, from modern lavas, 268 NEBULAR hypothesis of Laplace, 325, 352 — — of Kant, 352 New Zealand, geysers of, 217 — — volcanoes of, 135 — — volcanic cones in, 79 Niedermendig, lava of, 103 Nordenskiöld, Professor, cited, 318 OBSERVATORY on Vesuvius, 24, 37 — on Etna, 37 Obsidian, 59 Oceans, depth of, in volcanic areas, 242 Oceanic islands, volcanoes in, 228 Oliver, Capt. S. P., 92 Oldhamite, 314 Outlines of Vesuvius, 87, fig. 17 Ovifak, iron-masses of, 319 Oxidation of materials of globe, 324 Oxygen, proportion in lavas, 47 PACIFIC, volcanoes in, 229 Palmieri, Professor, cited, 25, 37 Papandayang, eruption of, 169 Papin's digester, nature of action in, 22 Parasitic cones, formation of, 161, 162, fig. 61 Pele's Hair, 71 Perlitic structure, 109 Phillips, Mr. J. A., cited, 220 Phonolites, 50, 59 Phonolite-volcanoes, 126 Photograph of Vesuvius eruption, 24, fig. 5 'Pine-tree, appendage of Vesuvius, 29 Pitchstones, porphyritic, 60 Plateaux formed of lava-sheets, 270 Pliny, Elder, death of, 7 Plombières, hot springs of, 147 Plutonic rocks, 61 Pompeii, nature of materials covering, 117 Ponza Islands, 39 Ponza, sections in, 131, 132, figs. 51, 52 Porphyrites, 263 Porphyritic pitchstones, 60 Potentially liquid rock, 250 Pre-Cambrian volcanoes of British Islands, 274 Presence of water in lavas, 353 Pressure under which crystals were formed, 65 Predazzo, ancient volcano of, 165, fig. 67 Propylites, 199 Pseudo-dykes, 119 Pumice, how formed, 68 — cause of white colour of, 71 — floating on ocean, 73 — on ocean-beds, 73 Pumice-cones, 154 Puy de Pariou, Auvergne, 193, 194, figs. 82, 83 Puzzolana, 89 RAIN, accompanying volcanic outbursts, 30 Rate of movement of lava-streams, 97 Rath, Professor Vom, 72 Red clay of ocean-beds, 74 Red Mountains, Skye, 144 Reservoirs beneath volcanoes, 145 Reyer, Dr. Ed., experiments of, 125, 160 Reykjanes, eruption of, in 1783, 102 Rhyolites, 50, 59 Richthofen, Von, cited, 196, 199, 200, 205 Rocca-Monfina, 178, fig. 77 — —, 204 Rock-masses, movements of, 288 Rocky Mountains, 103 — — volcanoes of, 201 Rotomahana, sinter-terraces of, 185 Ropy-lavas, 98, fig. 24 SALINA, section in, 132, fig. 53 Sandwich Islands, lavas of, 125 San Sebastiano, destruction of, 26 San Stephano, section in, 131, fig. 50 Santorin, 42 Sarcoui, Grand Puy of, 126, fig. 44 Sciarra del fuoco, 13 Scoria, how formed, 68, 70 Scoria-cones, altered by acid gas, 155 — breached, 156 — characters of, 153 — preservation of, 155 — red colour of, 154 Scoria-cone in Vesuvius, 122, fig. 39 Scoria-cone near Auckland, N. Z., 165, fig. 66 Schmidt, referred to, 153 Schreibersite, 314 Scrope, Mr. Poulett, cited, 5, 69, 106, 135, 198, 205, 212, 238, 289 Sea of Azof, mud-volcanoes of, 182 Secchi, Father, cited, 362 Shiant Isles, 105 Silica, presence in lavas, 47 Silicates in lavas, 47 Silicon, proportion in lavas, 47 Siliceous sinter, deposits of, 220 Silver, spitting of, 355 Silvestri, Professor, cited, 230 Similarity of lavas of different ages, 260 Sinter-cones, forms of, 183, fig. 79 Skye, dissected volcano of, 144 Slags, compared with lavas, 46 Smith, Lawrence, cited, 320 Smoke, appearance of, due to steam, 2 Snowdon, 274 Solar prominences, 364-366, figs. 92, 93, 94 Solfatara of Naples, 214 Solfatara-stage of volcanoes, 215 Somma, 133 — crater-ring of, 83 Sorby, Mr. H. C., referred to, 59, 252 Spallanzani, early researches of, 4 — observations on Stromboli, 8 — cited, 39, 367 Specific gravities of lavas, 49 — — of glassy and crystalline rocks, 59 Spectroscope in vulcanology, 41 Spectrum-analysis, results of, 311 Specular-iron, deposited on lava-streams, 110 Sperenberg, boring of, 341 Sphærulites, 54, Frontispiece Sporadosiderites, 316 Stability of crust of globe, 326 Staffa, Isle of, 106 Steenstrup, cited, 319 Steam-engine compared to volcano, 8 Steam, emitted by lava of Vesuvius, 27 Sternberg, referred to, 113 St. Kilda, 181 Stokes, Professor, 65 St. Paul, Island of, 180 Stromboli, 42, 158 — apertures at bottom of crater, 15 — appearances in crater of, 16 — — at night, 10 — compared with Vesuvius, 23 — crater of, 13 — dependence of eruptions on atmospheric conditions, 34 — eruption of, 14, fig. 4 — general features of, 11 — map of, 11, fig. 2 — observations by Spallanzani, 8 — resemblance to flashing light, 10 — section of, 13, fig. 8 — soundings around, 12 — vapour-cloud above, 9 — violent eruptions of, 23 Strombolian stage, 23 Stufas, nature of, 217 Submarine volcanoes, 179 Subterranean forces, beneficial effects of, 303 Subsidence in centre of volcanoes, 165 Sulphur, absorption of water by molten, 356 — deposited on lava-streams, 110 — how formed at volcanoes, 18 — not the cause of volcanic outbursts, 18 Surfaces of lava-streams, 97-99, figs. 22, 23 Sun-spots, 361-363, figs. 89, 90, 91 Syenite, 59 Syssiderites, 316 Szabo, Professor, cited, 199 TACHYLYTE, 59 Tertiary volcanoes of British Islands, 276 Terraces, sinter- and travertine-formation of, 185, fig. 80 Temperature, increase in deeper parts of earth's crust, 335 — rate of increase in different areas, 340 Teneriffe, 44, 151 Teneriffe, 178, fig. 77 — peak of, 175, fig. 73 Tenon-and-mortise structure in basaltic columns, 107 Theodosius and Vulcano, 3 Thunder, accompanying volcanic outbursts, 28 Trachytes, 49, 50, 69 Trap-rocks, origin of, 241 Trass, 90 Travertine or Tibur-stone, 184 — deposits of, 220 Triassic volcanoes of British Islands, 275 Tridymite deposited on lava-streams, 110 Troilite, 314 Troost, cited, 355 Tufa, or tuff, 90 Tuff-cones, character of, 157 — denudation of, 157, 158 Typhon, fable of, 3 ULTRA-BASIC lavas, 50, 66 — rocks, 317 VAL DEL BOVE, Etna, 133, 180, 209 — — dykes in, 134, fig. 55 Vapour-cloud over Vesuvius, 26, 29 — — Stromboli, 9 Ventotienne, Island of, section at, 130, fig. 49 Vesuvius, 37 — changes in form of, 81 — compared with Stromboli, 23 — crater of in 1756, 84, fig. 14 — — of in 1767, 85, fig. 16 — — of in 1822, 82, fig. 13 — — of in 1843, 86, fig. 16 — detonations at, 26 — early history of, 83 — eruption of year 79, 84 — — of 1822, 69 — — of April 1872, 24 — — of October 1822, 24 — ejected blocks of, 45 — first eruption of, 7 — form of, 166 — fossils of, 45 — growth of cone of, 80 — history of, 204 — last eruption of, 7 — lava-stream of 1855, 101 — lava-streams of 1858, 1872, 97 — lavas of, 104 — minerals of, 46 — — ejected at, 149 — observatory on, 24, 37 — outlines of, 87 — pine-tree appendage of, 29 — scoria-cones in lava, 122 — — on lava of 1855, 153 — steam emitted by lava of, 27 — vapour-cloud over, 26, 29 Vesuvian stage, 23 — eruption, photograph of, 24, fig. 5 Viscid lavas of Lipari Islands, 94-96 Vitreous lavas, devitrification of, 259 Volcanic action, laws of, 32 — bombs, 70, 71 — cycles, nature of, 221, 222 — — duration of, 223 — cones, internal structure of, 115-122 — — experimental illustration of formation of, 120, fig. 37 — — limits to height of, 166 — — form of, 152 — — dimensions of, 152 — — irregular development of, 90 — — slopes of sides of, 91 — — composed of ejected rock-fragments, 156 — — curved slopes of, 156 — débris on sea-bottom, 240 — dust, fineness of, 69 — districts, areas of upheaval, 245 — ejections, alteration of, 258 — eruptions, compared to ebullition, 19, 20 — forces, compensate for denudation, 283 — — intensity at former periods, 278 — — necessity for action of, 285 — — shifting of from one area to another, 277 — mountains, origin of conical forms, 89 — — mode of growth, 89 — phenomena of the past similar to those at present, 273 — products, order of appearance of, 198, 199 Volcanic rocks, 61 — — similarity of ancient and modern, 253 Volcano, origin of name, 3 — craters of, 167 — Island of. See Vulcano. — compared to steam-engine, 8 Volcanoes, blocks, ejected from, 45 — built up of ejected fragments, 74 — destruction caused by, 281 — dissected by denudation, 115, 139 — erroneous ideas concerning, 1 — ejection of different materials from, 205 — known to ancients, 3 — life-history of, 186 — number of, 224, 225 — of Africa, 227 — of America, 236 — of Asia, 236 — of Bohemia, 126 — of Central Asia, 236 — of Central Pacific, 236 — of Europe, 227 — of Hungary, 126 — position in relation to mountain chains, 243 — popular ideas concerning, 1 — reservoirs beneath, 145 Volvic lava of, 103 Vose, cited, 346 Vulcan, forge of, 3 Vulcano, island of, 3, 158 Vulcano and Theodosius, 3 Vulcano, 178, fig. 77 — and Vulcanello, view of, 43, fig. 6 — chemical deposits at, 44 — eruption in 1786, 43 — — in 1873, 43 — — lava-stream in, 95, fig. 19 — —, 103, fig. 27 — plan of, 195, fig. 85 — section of volcanic cone in, 116, fig. 35 — section in, 129 — shifting of centre of eruption in, 196 Vulcanello, craters of, 197, fig. 86 Vulcanology, origin of the science, 4 — earliest treatise on, 5 WALFERDIN, M., cited, 340 Water in lavas, 353 — penetration through rocks, 358 — presence of in lavas, 102 — and saline solutions in cavities of crystals, 63 Werner, cited, 201 Western Isles of Scotland, 103, 139, 142 — — volcanoes of, 212 Whymper, Mr., 69 Woodward, Mr., experiments of, 119 Wrekin, ancient volcanic rocks of, 259 YOUNG, Professor, cited, 365 ZEOLITES, formation of, 150

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XXXV. VOLCANOES: what they are and what they teach. By John W. Judd, F.R.S. Fifth Edition. With 96 Illustrations.

XXXVI. SUICIDE: an Essay on Comparative Moral Statistics. By Professor H. Morselli. Third Edition.

XXXVII. The BRAIN and its FUNCTIONS. By J. Luys, Physician to the Hospice de la Salpêtrière. With numerous Illustrations. Third Edition.

XXXVIII. MYTH and SCIENCE: an Essay. By Tito Vignoli. Fourth Edition.

XXXIX. The SUN. By C. A. Young, Ph.D., LL.D. Fifth Edition. With numerous Illustrations.

XL. ANTS, BEES, and WASPS. A Record of Observations on the Habits of the Social Hymenoptera. By Sir John Lubbock, Bart., M.P. Fourteenth Edition. With 5 Chromo-lithographic Plates.

XLI. ANIMAL INTELLIGENCE. By George J. Romanes. LL.D., F.R.S. Sixth Edition.

XLII. The CONCEPTS and THEORIES of MODERN PHYSICS. By J. B. Stallo. Third Edition.

London: KEGAN PAUL, TRENCH, TRÜBNER, & CO., Ltd.

The International Scientific Series—continued.

XLIII. DISEASES of MEMORY. An Essay in the Positive Psychology. By Th. Ribot. Fourth Edition.

XLIV. MAN BEFORE METALS. By N. Joly, Correspondent de l'Institut de France. Fifth Edition. With 148 Illustrations.

XLV. The SCIENCE of POLITICS. By Prof. Sheldon Amos. Third Edition.

XLVI. ELEMENTARY METEOROLOGY. By Robert H. Scott. With 11 Plates and 40 Figures in Text. Seventh Edition.

XLVII. The ORGANS of SPEECH. By Georg Hermann von Meyer. With 47 Illustrations.

XLVIII. FALLACIES: a View of Logic from the Practical Side. By Alfred Sidgwick. Second Edition.

XLIX. The ORIGIN of CULTIVATED PLANTS. By Alphonse De Candolle. Second Edition.

L. JELLY FISH, STAR FISH, and SEA URCHINS. Being a Research on Primitive Nervous Systems. By G. J. Romanes, LL.D., F.R.S. Second Edition.

LI. The COMMON SENSE of the EXACT SCIENCES. By the late William Kingdon Clifford. Third Edition. With 100 Figures.

LII. PHYSICAL EXPRESSION: its Modes and Principles. By Francis Warner, M.D., F.R.C.P. Second Edition. With 50 Illustrations.

LIII. ANTHROPOID APES. By Robert Hartmann. With 63 Illustrations. Second Edition.

LIV. The MAMMALIA in their RELATION to PRIMEVAL TIMES. By Oscar Schmidt. Second Edition. With 51 Woodcuts.

LV. COMPARATIVE LITERATURE. By H. Macaulay Posnett, LL.D.

LVI. EARTHQUAKES and other EARTH MOVEMENTS. By Prof. John Milne. With 88 Figures. Fourth Edition, revised.

LVII. MICROBES, FERMENTS, and MOULDS. By E. L. Trouessart. With 107 Illustrations. Third Edition.

LVIII. GEOGRAPHICAL and GEOLOGICAL DISTRIBUTION of ANIMALS By Prof. A. Heilprin. Second Edition.

LIX. WEATHER: a Popular Exposition of the Nature of Weather Changes from Day to Day. By the Hon. Ralph Abercromby. With 96 Figures. Fourth Edition.

LX. ANIMAL MAGNETISM. By Alfred Binet and Charles Fére. Fourth Edition.

LXI. MANUAL of BRITISH DISCOMYCETES, with descriptions of all the Species of Fungi hitherto found in Britain included in the Family, and Illustrations of the Genera. By William Phillips, F.L.S. Second Edition.

LXII. INTERNATIONAL LAW. With Materials for a Code of International Law. By Professor Leone Levi.

LXIII. The GEOLOGICAL HISTORY of PLANTS. By Sir J. William Dawson. With 80 Illustrations.

LXIV. The ORIGIN of FLORAL STRUCTURES THROUGH INSECT and other AGENCIES. By Prof. G. Henslow. Second Edition.

LXV. On the SENSES, INSTINCTS, and INTELLIGENCE of ANIMALS, with special reference to INSECTS. By Sir John Lubbock, Bart., M.P. With 118 Illustrations. Third Edition.

London: KEGAN PAUL, TRENCH, TRÜBNER, & CO., Ltd.

The International Scientific Series—continued.

LXVI. The PRIMITIVE FAMILY in its ORIGIN and DEVELOPMENT. By C. N. Starcke. Second Edition.

LXVII. PHYSIOLOGY of BODILY EXERCISE. By Fernand Lagrange, M.D. Second Edition.

LXVIII. The COLOURS of ANIMALS: their Meaning and Use, especially considered in the case of Insects. By E. B. Poulton, F.R.S. With Chromolithographic Frontispiece and upwards of 60 Figures in Text. Second Edition.

LXIX. INTRODUCTION to FRESH-WATER ALGÆ. With an Enumeration of all the British Species. By M. C. Cooke, LL.D. With 13 Plates Illustrating all the Genera.

LXX. SOCIALISM: NEW and OLD. By William Graham, M.A., Professor of Political Economy and Jurisprudence, Queen's College, Belfast. Second Edition.

LXXI. COLOUR-BLINDNESS and COLOUR-PERCEPTION. By F. W. Edridge-Green, M.D. With 3 Coloured Plates.

LXXII. MAN and the GLACIAL PERIOD. By G. F. Wright, D.D. With 111 Illustrations and Maps. Second Edition.

LXXIII. HANDBOOK of GREEK and LATIN PALÆOGRAPHY. By Sir E. Maunde Thompson, K.C.B. With Tables of Alphabets and Facsimiles. Second Edition.

LXXIV. A HISTORY of CRUSTACEA: Recent Malacostraca. By Thomas R. R. Stebbing, M.A. With 19 Plates and 32 Figures in Text.

LXXV. The DISPERSAL of SHELLS: an Inquiry into the means of Dispersal possessed by Fresh Water and Land Mollusca. By H. Wallis Kew, F.Z.S. With Preface by A. R. Wallace, F.B.S., and Illustrations.

LXXVI. RACE and LANGUAGE. By André Lefèvre, Professor in the Anthropological School, Paris.

LXXVII. The ORIGIN of PLANT STRUCTURES by SELF-ADAPTATION TO THE ENVIRONMENT. By Rev. G. Henslow. M.A., F.L.S., F.G.S., &c., author of 'The Origin of Floral Structures,' &c.

LXXVIII. ICE-WORK PRESENT and PAST. By Rev. T. G. Bonney, D.Sc., LL.D., F.R.S., &c., Professor of Geology at University College, London; Fellow of St. John's College, Cambridge.

LXXIX. A CONTRIBUTION to our KNOWLEDGE of SEEDLINGS. By Rt. Hon. Sir John Lubbock, Bart., M.P., F.R.S.

LXXX. The ART of MUSIC. By Sir C. Hubert H. Parry, Mus. Doc.

LXXXI. The POLAR AURORA. By Alfred Angot. Illustrated.

LXXXII. WHAT is ELECTRICITY? By J. Trowbridge. Illustrated.

LXXXIII. MEMORY. By F. W. Edridge-Green, M.D. With Frontispiece.

LXXXIV. The ELEMENTS of HYPNOTISM. By B. Harry Vincent. With Diagrams. Second Edition.

LXXXV. SEISMOLOGY. By John Milne, F.R.S., F.G.S., &c., Author of 'Earthquakes.' With 63 Figures.

LXXXVI. On BUDS and STIPULES. By the Right Hon. Sir John Lubbock, Bart, M.P., F.R.S., D.C.L., LL.D. With 4 Coloured Plates and 340 Figures in the Text.

LXXXVII. EVOLUTION by ATROPHY, in Biology and Sociology. By Jean Demoor, Jean Massart, and Emile Vandervelde. Translated by Mrs. Chalmers Mitchell. With 84 Figures.

London: KEGAN PAUL, TRENCH, TRÜBNER, & CO., Ltd.