CHAPTER II.

PHYSICAL HISTORY OF CAVES.

Caves formed by the Sea and by Volcanic Action 23

Caves in Arenaceous Rocks 24

Caves in Calcareous Rocks of various ages 25-27

Their Relation to Pot-holes, “Cirques,” and Ravines 27, 28

Water-Cave of Wookey Hole 29-31

Goatchurch Cave 31-34

Water-Caves of Derbyshire 34

Water-Caves of Yorkshire--Ingleborough 35-39

Rate of Deposit of Stalagmite 39-41

Descent into Helln Pot 41-47

Caves and Pots round Weathercote 47-50

Formation of Caves, Pot-holes, and Ravines 50-57

Caverns not generally formed in line of Faults 57

Various Ages of Caves 58-61

Filling up of Caves 61

Cave of Caldy 62-68

Black-Rock Cave, Tenby 68

Carbonate of Lime dissolved by Atmospheric Water 69-70

Circulation of Carbonate of Lime 71

Temperature of Caves 71-72

Conclusion 73