258 THE BORDERLAND OF SCIENCE. 



may be that so violent was the first upward movement, 

 that the upper parts of all buildings were flung into the 

 air, whence not partaking in the horizontal move- 

 ment which displaced the foundations and lower part 

 of the houses they fell in ruins over the debris of 

 buildings they had not belonged to originally. An 

 upward, followed by a downward, and then by a hori- 

 zontal movement, might result in either form of de- 

 molition, or in both. 



A short time after the destruction of Eiobamba, a 

 fearful subterranean rumbling, resembling the loudest 

 thunder-peals, was heard under the cities of Quito and 

 Ibarra, the former more than a hundred miles from 

 Eiobamba. 



The subterranean noises heard during earthquakes 

 are sometimes singularly striking. The nature of the 

 noises is very various, says Humboldt, ' rolling, rattling, 

 clanking like chains, occasionally like thunder close at 

 hand ; or it is clear and ringing, as if masses of 

 obsidian or other vitrified matters were struck in 

 caverns underground.' These noises are not only 

 heard much farther off than they could be if they were 

 transmitted in the air, but they travel much more 

 rapidly. In 1744, when the great eruption of Cotopaxi 

 took place, subterranean noises were heard at Honda, 

 on the Rio Maddalena. The crater of Cotopaxi, 17,000 

 feet above the level of Quito, is separated from it * by 

 the colossal mountain-masses of Quito, Pasto, and 

 Papayan, by innumerable valleys and precipices, and 

 by an actual distance of no less than 500 geographical 



