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64: 



ERUPTION IN THE CANARY ISLANDS. 



[CiL XXVII. 



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Magazine for 1835, p, 642, and for 1838, p. 361^ and m tlie 

 Comptes Eendus^ April^ 1838^ accounts are given of a series 

 of volcanic phenomena, earthquakes, troubled water, floating 

 scorise and columns of smoke, which have been observed at 

 intervals since the middle of the last century, in a space of 

 open sea between longitudes 20° and 22° west, about half a 

 degree south of the equator. These facts, says Mr. Darwin, 

 seem to show, that an island or an archipelago is in process 

 of formation in the middle of the Atlantic : a line joinino* 

 St. Helena and Ascension would, if prolonged, intersect this 

 slowly nascent focus of volcanic action."^ Should land be 

 eventually formed here, it will not be the first that has been 

 produced by igneous action in this ocean since it 

 inhabited by the existing species of testacea. At Porto Praya 

 in St. Jago, one of the Azores, a horizontal, calcareous 

 stratum occurs, containing shells of recent marine species, 

 covered by a great sheet of basalt 80 feet thick. f It 

 would be difficult to estimate too highly the commercial and 

 political importance which a group of islands might acquire, 

 if in the next two or three thousand years they should rise in 

 mid-ocean between St. Helena and Ascension. 



Eruption in Lancerote^ 1730 to 1736. — An eruption hap- 

 pened in Lancerote, one of the Canary Islands, between the 

 years 1730 and 1736, of which a detailed description was 

 published by Von Buch, who visited that island in 1815, and 

 compared the accounts transmitted to us of the event, with 

 the present state and geological appearances of the country. 

 During this outbreak, which lasted for five successive years, 

 the flourishing town of St. Catalina and several other places 

 were buried under lava and scoriae 400 feet in thickness. 

 Thirty cones were thrown up arranged in one line running 

 nearly east and west and 

 geographical miles. The most elevated of these hills reached 

 a height of about 600 feet above its base. The subterranean 

 cleft from which elastic fluids escaped seems to have opened 

 or widened at a succession of new points when the first 

 apertures had become obstructed by solid lava or ejected 



extending for a length of tAVO 



^ Darwin's Volcanic Islands, p. 92. 



t Ibicl. p. 6. 



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