^82 Mr Forbes*s Physical Notices of the Bay of Naples. 



quakes succeeded one another with fearful rapidity, and hav- 

 ing for two months kept the inhabitants in a state of constant 

 alarm, terminated at last in the great eruption of 1302. The 

 crater, as we have observed, was not in Monte Epomeo, but 

 the lava found its exit near the eastern side of the island, at 

 no great height above the sea, from a point named still the 

 " Campo del Arso." It is not very far from the town of Ts- 

 chia or Celso, and runs quite down to the sea at no great dis- 

 tance from Casamicciola. Its hardness and sterility is quite 

 remarkable, and is a striking example of the danger of theoriz- 

 ing upon the dates of eruptions by the forwardness of the decom- 

 position of their products : during 500 years it has made less 

 progress than some of those of Vesuvius probably within the 

 last twenty. The length of the stream is a mile and a half, 

 when it joins the sea, and its breadth half a mile ; its colour 

 varies from iron-grey to reddish-black, and is remarkable for 

 the glassy felspars which it contains. Spallanzani remarks, 

 that it appears to have been produced under extremely violent 

 heat from the fusion of some of the crystals of felspar; in a 

 specimen which I broke, the augite was collected in crystalline 

 patches. Bolomieu relates that the eruption continued for two 

 years, and is surprised at the want of pumices here observed ; 

 but pumice was discovered by Spallanzani, who imputes it to 

 the action of heat on the hornstone, of which, according to him, 

 the base of the lava is formed. The time during which the erup- 

 tion and its accompaniments lasted, is one of its most remark- 

 able features : the surviving inhabitants (many having been kil- 

 led by the catastrophe,) deserted the island for a long period, 

 and actually did not return till the year 1305. The accounts 

 we have received of this eruption are by no means very satis- 

 factory, and seem to be chiefly derived from an old author 

 Villani, who wrote a history of Florence. 



Since the fourteenth century, Ischia appears not to have 

 been the scene of any very striking indications of volcanic 

 agency, and we are not even informed whether the formation 

 of the Monte Nuovo in 1538 occasioned any corresponding 

 paroxysm. Earthquakes in that country, unless very violent, 

 do not produce much attention, nor are even put on record ; 

 one, however, we may mention, from its recent occurrence, as 



