284 REACTION OF THE INTERIOR OF THE EARTH 



The volcanoes of Java, like most of the linear groups 

 of volcanoes, present the important phenomenon, that 

 simultaneity of eruption is much more rarely observed in 

 cones adjacent to each other than in those which are far 

 apart. When, in the night of the llth of August 

 1772, the volcano Grunung Pepandajan (7034 feet high) 

 broke out into the most destructive eruption with which 

 the island of Java has ever been visited within historic 

 times, in the same night (llth to 12th of August) two 

 other volcanoes, Or. Tjerimai and Or. Slamat, which are 

 situated respectively 184 and 352 geographical miles in a 

 direct line from Or. Pepandajan( 415 ), also became ignited. 

 Admitting the whole series of volcanoes to be over one 

 and the same hearth, yet assuredly the network through 

 which they communicate is so complicated, that the ob- 

 struction of ancient channels of vapour, or, in the course 

 of centuries, the temporary opening of new ones, 

 render conceivable a simultaneous outbreak at very 

 distant points. I may here recall the circumstance of 

 the sudden disappearance of the column of smoke from 

 the volcano of Pasto, on the morning of the 4th of 

 February 1797, when the dreadful earthquake of Kio- 

 bamba shook the high plain of Quito between Tungura- 

 hua and. Cotopaxi. ( 416 ) 



The volcanoes of Java are described as having gene- 

 rally a ribbed character, to which I have never seen 

 anything similar in the Canaries, in Mexico, or in the 

 Cordilleras of Quito. The traveller already alluded to, 

 to whom we owe such excellent observations on the 

 structure of volcanoes, the" geography of plants, and the 

 psychrometric relations of humidity in Java, has de- 

 scribed this phenomenon with such remarkable clear- 



