TKUE VOLCANOES. 267 



such extent that " Sicily and the sea-girt heights above 

 Cumse (called Phlegra, or the burnt field,) lie upon the 

 shaggy breast of the monster." 



Thus Typhon (the raging Enceladus) was, in the popular 

 fancy of the Greeks, the mythical symbol of the unknown 

 cause of volcanic phenomena lying deep in the interior of 

 the earth. By the position and the space which he occupied 

 were indicated the limitation and the co-operation of parti- 

 cular volcanic systems. In the fanciful geological picture of 

 the interior of the earth, in the great contemplation of the 



surface of the earth as the mightiest of moving forces (Aristotle, 

 Meteorol. ii, 8, 3), the wind, the inclosed pneuma, was recognised as the 

 universal cause of vulcanicity (of fire-vomiting mountains and earth- 

 quakes). Aristotle's contemplation of nature was founded upon the 

 mutual action of the external and the internal subterranean air, upon 

 a theory of transpiration, upon differences of heat and cold, moisture 

 and dryness (Aristotle, Meteor, ii, 8, 1, 25, 31, and ii, 9, 2). The greater 

 the mass of the wind inclosed " in subterranean and submarine pas- 

 sages," and the more it is obstructed in its natural, essential property of 

 moving far and quickly, the more violent are the eruptions. " Vis 

 fera ventorum, csecis iuclusa cavernis" (Ovid, Metamorph. xv, 299). 

 Between the wind and the fire there is a peculiar relation. (To Tri'p 

 orav /itrd TTVIVHCLTOQ y, yivtrai <p\b% KOI (ptptrai Ta\kw^ ; Aristotle, 

 Meteorol. ii, 8, 3. KCLI yap TO irvp olov irvivfiaroQ TIQ <j>vait; ; Theo- 

 phrastus, De Igne, 30, p. 715). The wind (pneuma) suddenly set 

 free from the clouds, sends the consuming and widely luminous 

 lightning flash (Tro/jcrrTyp). " In the Phlegrsea, the Katakekaumene of 

 Lydia," says Strabo (lib. xiii, p. 628), "three chasms, fully forty 

 stadia from each other, are still shown, which are called the wind- 

 bags ; above them lie rough hills, which are probably piled up by the 

 red-hot masses blown up." He had already stated (lib. i, p. 57) "that 

 between the Cyclades (Thera and Therasia) flames of fire burst forth 

 from the sea for four days together, so that the whole sea boiled and 

 burnt ; and an island composed of calcined masses was gradually raised 

 as if by a lever." All these well described phenomena are ascribed 

 to the compressed wind, acting like elastic vapours. Ancient physical 

 science troubled itself but little about the peculiar essentials of mate- 

 rial bodies; it was dynamic, and depended on the measure of the moving 

 force. We find the opinion that the increasing heat of the planet with 

 the depth is the cause of volcanoes and earthquakes, first expressed 

 towards the close of the third century by a Christian bishop in Africa 

 tinder Diocletian (Cosmos, vol. v, p. 196). The Pyriphlegethon of 

 Plato, as a stream of fire circulating in the interior of the earth, 

 nourishes all lava-giving volcanoes, as we have already mentioned 

 in the text. In the earliest presentiments of humanity, in a narrow 

 circle of ideas, lie the germs of that which we now think we may 

 explain under the form of other symbols. 



