Eruption of 1883 3 



rattle and shook the houses to such an extent that objects were 

 thrown from tables. 



During the eruption the volcano covered the whole neighbour- 

 hood for a distance of 3o kilometres [22 miles] with glowing stones 

 and hot ashes. Near the centre of activity, on the island of Sebesi, 

 with 2000 inhabitants, villages suffered the fate of Herculaneum 

 and Pompeii. A dense rain of ashes fell over the whole of South 

 Sumatra, to Benkoelen and Palembang in the north, in West Java 

 beyond Batavia and the residency of Preanger, while the finer dust 

 was spread over a much greater area amounting approximately to 

 600,000 square kilometres [234,000 square miles]. In a south-westerly 

 direction the rain of ashes extended 1200 kilometres [750 miles], 

 and it is well known that the finest particles mixed with aqueous 

 vapour and suspended in the upper region of the atmosphere were 

 carried round the world and caused the wonderful twilight effects 

 which were observed everywhere in December 1883 1 . The total 

 amount of material thrown out from the craters of Krakatau from 

 May to August 1883 was estimated by Verbeek, after careful calcu- 

 lation, at 18 cubic kilometres [4'4 cubic miles]. As a result of this 

 enormous loss of material the chief crater and adjacent parts of the 

 island were undermined and on the morning of August 27th the 

 climax was reached : a large portion of the island and of the 

 surrounding sea-floor fell in like an insufficiently supported vault. 

 The sea was drawn after the debris from all sides into a funnel-like 

 depression and, surging up again over the submerged crater, produced 

 gigantic waves which rose to a height of 40 metres [131 ft.] and, carrying 

 with them blocks of rock which reached 300 cubic metres in bulk, broke 

 repeatedly on the coasts of Java and Sumatra. For a distance of several 

 kilometres inland everything was destroyed ; whole villages disap- 

 peared and about 30,000 people were drowned. In the shallow Java Sea 

 the waves acquired less force. The low islands in the Bay of Batavia 

 suffered considerable damage and in Tandjong Priok, in the harbour 

 of Batavia, from midday on August 27th for the next 36 hours as 

 many as 18 seismic waves were recorded, the first and highest of 

 which reached a height of more than 2 metres. On the same day 

 large waves were produced in all the harbours of the Indian Ocean 

 where the deeper water furnished much more favourable conditions 

 for their transmission. By August 28th the seismic waves had found 

 their way into the North Atlantic Ocean and were recorded at 

 Rochefort, Cherbourg, Havre and other places 2 . 



The geological expedition conducted by Verbeek, which under- 



P See Part IV. and PI. XXXVI., Rep. Roy. Soc. Committee.] 

 [ 2 See Report Roy. Soc. Com. Part III.] 



12 



