262 COSMOS. 



original cultivated plain ; but almost four times that of 

 the crater of elevation (Monte Nuovo) in the Phlegrsean 

 Fields, to which Scacchi 67 ascribes a height of 432 feec 

 from accurate measurement. The permanent activity of 

 the volcano of Izalco, which was long considered as a 

 safety-valve for the neighbourhood of San Salvador, did 

 not however preserve the town from complete destruction 

 on Easter eve in this year (1854). 



One of the Cape Yerd Islands, which rises between S. Jago 

 and Brava, early received from the Portuguese the name of 

 llha do Fogo, because, like Stromboli, it produced fire uninter- 

 ruptedly from 1680 to 1713. After a long repose, the vol- 

 cano of this island resumed its activity in the summer of 

 the year 1798, soon after the last lateral eruption of the 

 Peak of Teneriffe in the crater of Chahorra, which is errone- 

 ously denominated the volcano of Chahorra as if it were a 

 distinct mountain. 



The most active of the South American volcanoes, and 

 indeed of all those which I have here specially indicated, is 

 the Sangay, which is also called the Volcan de Macas, because 

 the remains of this ancient city, so populous in the early 

 period of the Conquista, are situated upon the Rio TJpano, 

 only 28 geog. miles to the south of it. The colossal mountain, 

 17,128 feet in height, has risen on the eastern declivity of 

 the eastern Cordillera, between two systems of tributaries of 

 the Amazons, those of the Pastaza and the TJpano. The 

 grand and unequalled fiery phenomenon which it now ex- 

 hibits, appears only to have commenced in the year 1728. 

 During the astronomical measurements of degrees by Bou- 

 guer and La Condamine (1738 to 1740), the Sangay served 

 as a perpetual fire signal. 68 In the year 1802, I myself 

 heard its thunder for months together, especially in the 

 early morning, in Chillo, the pleasant country seat of the 

 Marquis de Selvaletjre near Quito, as half a century pre- 

 viously, Don Jorge Juan had perceived the ronquidos del 



57 Memorie geologiche sulla Campania, 1849, p. 61. I found the 

 height of the volcano of Jorullo to be 1682 feet above the plain in 

 which it rose, and 4266 feet above the sea-level. 



58 La Condamine, Journal du Voyage a VEquateur, p. 163; and in 

 the Mesure de Trois Degres de la Meridienne de I' Hemisphere Austral, 

 p. 56. 



