198 LIGHT SCIENCE FOR LEISURE HOURS. 



About three hours after the earthquake in other 

 words, at about eight o'clock in the evening an in- 

 tensely brilliant light made its appearance above the 

 neighbouring mountains. It lasted for fully half an 

 hour, and has been ascribed to the eruption of some as 

 yet unknown volcano. 



At Arica the sea-wave produced even more destruc- 

 tive effects than had been caused by the earthquake. 

 About twenty minutes after the first earth-shock, 

 the sea was seen to retire, as if about to leave 

 the shores wholly dry ; but presently its waters re- 

 turned with tremendous force. A mighty wave, whose 

 length seemed immeasurable, was seen advancing like 

 a dark wall upon the unfortunate town, a large part 

 of which was overwhelmed by it. Two ships, the 

 Peruvian corvette 'America' and the United States 

 1 double-ender ' ' Watertree,' were carried nearly half a 

 mile to the north of Arica, beyond the railroad which 

 runs to Tacna, and there left stranded high and dry. 

 This enormous wave was considered by the English 

 vice-consul at Arica to have been fully fifty feet in 

 height. 



At Chala, three such waves swept in after the first 

 shocks of earthquake. They overflowed nearly the 

 whole of the town, the sea passing more than half a 

 mile beyond its usual limits. 



At Islay and Iquique similar phenomena were mani- 

 fested. At the former town the sea flowed in no less 

 than five times, and each time with greater force. 

 Afterwards the motion gradually diminished, but even 



