Imágenes de páginas
PDF
EPUB

FIG.

LIST OF ILLUSTRATIONS.

1. Weathering of rock, as shown by old masonry. (The "falsebedding" and other original structures of the stone are revealed by weathering).

PAGE

16

[blocks in formation]

7. Erosion of limestone by the solvent action of a peaty stream,

Durness, Sutherlandshire

33

8. Pot-holes worn out by the gyration of stones in the bed of a stream 9. Grand Cañon of the Colorado

40

44

10. Gullies torn out of the side of a mountain by descending torrents,

with cones of detritus at their base

47

11. Flat stones in a bank of river-shingle, showing the direction of

[blocks in formation]

14. Alluvial terraces on the side of an emptied reservoir

[blocks in formation]

17. Piece of shell-marl containing shells of Limnæa peregra

62

18. View of Axmouth landslip as it appeared in April 1885

69

19. Section of cavern with stalactites and stalagmite

72

20. Section showing successive layers of growth in a stalactite.

[blocks in formation]

23. Perched blocks scattered over ice-worn surface of rock

86

24. Stone smoothed and striated by glacier-ice

89

25. Ice-striation on the floor and side of a valley

90

26. Buller of Buchan-a caldron-shaped cavity or blow-hole worn

out of granite by the sea on the coast of Aberdeenshire.

95

27. The Stacks of Duncansby, Caithness, a wave-beaten coast-line 28. Section of submarine plain

97

100

29. Storm-beach ponding back a stream and forming a lake; west

coast of Sutherlandshire

103

[merged small][merged small][merged small][ocr errors]

31. Diatom-earth from floor of Antarctic Ocean, magnified 300

[blocks in formation]

35. Cellular lava with a few of the cells filled up with infiltrated

mineral matter (Amygdules)

130

36. Section of a lava-current

131

37. Elongation of cells in direction of flow of a lava-stream

132

38. Volcanic block ejected during the deposition of strata in water

137

39. Volcanoes on lines of fissure

139

40. Outline of a volcanic neck

142

41. Ground-plan of the structure of the Neck shown in Fig. 40

142

42. Section through the same Neck as in Figs. 40 and 41

143

43. Volcanic dykes rising through the bedded tuff of a crater

145

44. Group of quartz-crystals (Rock-crystal)

157

45. Calcite (Iceland spar) showing its characteristic rhombohedral

[blocks in formation]

53. Piece of hæmatite, showing the nodular external form and the

internal crystalline structure

172

54. Octahedral crystals of magnetite in chlorite schist

173

55. Dendritic markings due to arborescent deposit of earthy manganese

oxide

174

56. Cavity in a lava, filled with zeolite which has crystallised in long

[blocks in formation]

61. Sphærosiderite or Clay-ironstone concretion enclosing portion of

[blocks in formation]

65. Section of a septarian nodule, with coprolite of a fish as a nucleus 188

[blocks in formation]

FIG.

PAGE

72. Schistose structure

194

73. Brecciated structure-volcanic breccia, a rock composed of angular fragments of lava, in a paste of finer volcanic debris

197

[blocks in formation]

77. Group of crystals of felspar, quartz, and mica, from a cavity in

the Mourne Mountain granite

216

78. Columnar basalts of the Isle of Staffa, resting upon tuff (to the

[blocks in formation]

83. Cast of a sun-cracked surface preserved in the next succeeding

layer of sediment

233

84. Rain-prints on fine mud

234

85. Vertical trees (Sigillaria) in sandstone, Swansea (Logan)

[blocks in formation]

94. Curved strata (anticlinal fold), near St. Abb's Head

251

95. Curved strata (synclinal fold), near Banff

252

96. Anticlines and Synclines

253

97. Section of the Grosse Windgälle (10,482 feet), Canton Uri,

Switzerland, showing crumpled and inverted strata (after Heim) 254

[blocks in formation]

101. Sections to show the relations of Plications to reversed

Faults

258

102. Throw of a Fault

:

259

103. Ordinary unaltered red sandstone, Keeshorn, Ross-shire

260

104. Sheared red sandstone forming now a micaceous schist, Kee

shorn, Ross-shire

260

105. Outline and section of a Boss traversing stratified rocks

265

106. Ground-plan of Granite-boss with ring of Contact-Meta

[blocks in formation]
[blocks in formation]

115. A, Fucoid-like impression (Eophyton Linneanum) from Cam

brian rocks (3). B, An Upper Silurian sea-weed (Chondrites
verisimilis), natural size

319

116. Oldhamia radiata (natural size), Ireland

321

[blocks in formation]

123. Filled-up Burrows or Trails left by a sea-worm on the bed of

[blocks in formation]

140. Section of part of the Cape Breton coalfield, showing a succes

[blocks in formation]
[blocks in formation]
« AnteriorContinuar »