6l8 PHILOSOPHICAL TRANSACTIONS. [aNNO 1780, 



volcanic matter rose and fell in a more perpendicular direction, and Ottaiano did 

 not suffer by the day's eruption ; but most of the inhabitants of ihe towns, on 

 the borders of Vesuvius, fled to Naples, alarmed by the tremendous clouds and 

 the loud explosions. Sir W. remarked, that several very large stones, after 

 having mounted an immense height, formed a parabola, leaving behind them a 

 trace of white smoke that marked their course: some burst in the air exactly like 

 bombs, and others fell into the valley between Somma and Vesuvius without 

 bursting; others again burst into a thousand pieces soon after their emission 

 from the crater: they might very properly be called volcanic bombs. 



On the whole, this day's eruption was very alarming: until the lava broke out, 

 about 2 o'clock, and ran 3 miles between the 2 mountains, they were in 

 continual apprehension of some fatal event. It continued to run about 3 

 hours, during which time every other symptom of the mountain fever gradually 

 abated, and at 7 at night all was calm. It was universally remarked, that the 

 air this night for many hours after the eruption, was filled with meteors, such as 

 are vulgarly called falling stars; they shot generally in a horizontal direction, 

 leaving a luminous trace behind them, but which quickly disappeared. 



August 11, about 6 in the morning, the 5th and last fever-fit of the moun- 

 tain came on, and gradually increased. About 12 o'clock it was at its height, 

 and very violent indeed, the explosions being louder than those that attended 

 the former eruptions. The same mountains of white cotton-like clouds, piled 

 one over another, rose to such an extraordinary height, and formed such a 

 colossal mass over Vesuvius, as cannot possibly be described, or scarcely 

 imagined. It may have been from a scene of this kind, that the ancient poets 

 took their ideas of the giants waging war with Jupiter. About 5 in the evening 

 the eruption ceased, some rain having fallen this day, which having been greatly 

 impregnated with the corrosive salts of the volcano, did much damage to the 

 vines in its neighbourhood. 



August 1 5, Sir W. went to visit Ottaiano and Caccia-bella, the district which 

 had been most severely treated by the heavy and destructive shower of volcanic 

 matter from the crater of Vesuvius on the 8th. Soon after having passed the town 

 of Somma, he began to perceive, that the heat of the fiery shower, which had 

 fallen in its neighbourhood, had affected the leaves of the trees and vines, which 

 were more parched and shrivelled in proportion as he approached the town of 

 Ottaiano, which may be about 3 miles from Somma. At about the distance of 

 a mile from Somma, he began to perceive fresh cinders or scoriae of lava, thinly 

 scattered on the road and in the fields. At every step advanced he found them 

 of a larger dimension, and in greater abundance. At the distance of a mile 

 and a half from Ottaiano, the soil was totally covered by them, and the leaves 

 and fruits were either entirely stripped from the trees, or remained thinly on 



