VOLCANO OF JORULLO. 293 



experiencing much danger from the brittleness of 

 the lava. 



The formation of this volcano is one of the most 

 extraordinary phenomena which have been observed 

 on our globe. The plain of Malpais, covered with 

 small cones from six to ten feet in height, is part of 

 an elevated table-land bounded by hills of basalt, 

 trachyte, and volcanic tufa. From the period of 

 the discovery of America to the middle of the last 

 century, this district had underjoone no change of 

 surface, and the seat of the crater was then covered 

 with a plantation of indigo and sugar-cane ; when, 

 in June, 1759, hollow sounds were heard, and a suc- 

 cession of earthquakes continued for two months, 

 to the great consternation of the inhabitants. From 

 the beginning of September every thing seemed to 

 announce the re-establishment of tranquillity ; but 

 in the night of the 28th the frightful subterranean 

 noises again commenced. The Indians fled to the 

 neighbouring mountains. A tract not less than from 

 three to four square miles in extent rose up in the 

 shape of a dome ; and those who witnessed the phe- 

 nomenon asserted, that flames were seen issuing 

 from a space of more than six square miles, while 

 fragments of burning rocks were projected to an 

 immense height, and the surface of the ground un- 

 dulated like an agitated sea. Two brooks which 

 watered the plantations precipitated themselves into 

 the burning chasms. Thousands of the small cones 

 described above suddenl}" appeared, and in the midst 

 of these eminences, called hornitos or ovens, six great 

 masses, having an elevation of from 1312 to 1640 

 feet above the original level of the plain, sprang up 

 from a gulf running from N.N.E. to S.S.W. The 

 most elevated of these mounds is the great volcano 

 of JoruUo, which is continually burning. The erup- 

 tions of this central volcano continued till February, 

 1760, when they became less frequent. The Indians, 

 who had abandoned all the villages within thirty 



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