EARTHQUAKES. 173 



of 1348 English miles), the velocity obtained was 89*26 

 miles in a minute, or 7953 feet in a second ; which, how- 

 ever, is still 3438 feet less than in cast iron.* 



Concussions of the earth and sudden eruptions of fire from 

 volcanoes which have been long in repose, whether these 

 merely emit cinders, or, like intermittent springs, pour forth 

 fused, fluid earths in streams of lava, have certainly a single, 

 common causal connection in the high temperature of the in- 

 terior of our planet ; but one of these phenomena is usually 

 manifested quite independently of the other. Thus, in the 

 chain of the Andes in its linear extension, violent earth- 

 quakes shake districts in which unextinguished, often indeed 

 active, volcanoes exist without the latter being perceptibly 

 excited. During the great catastrophe of Riobamba, the 

 volcanoes of Tunguraliua and Cotopaxi — the fbrmer in the 

 immediate vicinity, and the latter rather farther off — re- 

 mained perfectly quiet. On the other hand, volcanoes have 

 presented violent and long-continued eruptions without any 

 earthquake being perceived in their vicinity, either previous- 

 ly or simultaneously. In fact, the most destructive earth- 

 quakes recorded in history, and which have passed through 

 many thousand square miles, if we may judge from what is 

 observable at the surface, stand in no connection with the 



* Julius Schmidt, in No.!Ji;geratli, Ueher das Erdhehen vom 29 JuU^ 

 18-1:6, s. 28-37. With the velocity stated in the text, the earthquake 

 of Lisbon would have passed round the equatorial circumference of 

 the earth in about 45 hours. Michell {Phil. Transact, vol. i., pt. ii., 

 p. 572) found for the same earthquake of the 1st November, 1755, a 

 velocity of only 50 English miles in a minute — that is, instead of 7956, 

 only 4444 feet in a second. The inexactitude of the older observa- 

 tions and difference in the direction of propagation may conduce to 

 this result. Upon the connection of Neptune Avith earthquakes, at 

 which I have glanced in the text (p. 181), a passage of Proclus, in the 

 commentary to Plato's Cratylus, throws a remarkable light. " The 

 middle one of the three deities, Poseidon, is the cause of movement 

 in all things, even in the immovable. As the originator of movement 

 he is called 'Evvoacyaiog ; to him, of those who shared the empire of 

 Saturn, fell the middle lot, the easily-moved sea" (Creuzer, SymhoUh 

 und Mi/thologie, th. iii,, 1842, s. 260). As the Atlantis of Solon and 

 the Lyctonia, which, according to my idea, was nearly allied to it, are 

 geological myths, both the lands destroyed by earthquakes are regard- 

 ed as standing under the dominion of Neptune, and set in opposition 

 to the Saturnian continents. According to Herodotus (lib, ii., c. 43 

 et 50), Neptune was a Libyan deity, and unknown in Egypt. Upon 

 these circumstances — the disappearance of the Libyan lake Tritonis 

 by earthquake — and the idea of the great rarity of earthquakes in tha 

 valley of the Nile, see my Examen Critique de la Gcographie, t. i., p. 

 171 and 179. 



