Ambato was destroyed by an eruption of Cotopaxi in 1698, and has been badly damaged two or three times by earthquakes.
At the same time Cotopaxi and Sangay, the two active volcanoes, have actually increased in elevation since the measurement of La Condamine in 1742.
Sincholagua and Ruminagui are the next two peaks, going southward, and then the unrivalled cone of Cotopaxi - the highest active volcano in the world - from whose summit smoke curls upward unceasingly.
Tunguragua, or Tungurahua, has a cone-shaped summit like that of Cotopaxi, with a slope of 38°.
Iliniza, which stands west by north of Cotopaxi, has two pyramidal peaks, and is one of the most interesting mountains of the Ecuadorean group. It stands at the western end of the Tiupullo ridge, and overlooks the Quito basin to the north-east.
Farther north the rainfall becomes heavier, the plateau is covered with vegetation, and a considerable number of small rivers flow westward through the Cordillera to the Pacific. The Eastern Cordillera, or Andes, forms the water-parting between the two systems. The largest of the eastward-flowing rivers is the Napo, which rises in the eastern defiles of Cotopaxi and Sincholagua - the principal source being the Rio del Valle, which traverses the Valle Vicioso.
The Pastaza, or Pastassa, unlike the rivers already described, has its source on the central plateau west of the principal chain of the Andes, within the shadow of Cotopaxi, and breaks through the Cordillera to the north of Tunguragua.
One of its plateau tributaries, Rio Pedregal, rises on the slopes of Cotopaxi and is celebrated for its three beautiful cascades, the highest of which is about 220 ft.
Chimborazo, Iliniza, Pichincha), the ancient rocks of the Eastern Cordillera (Altar, Tunguragua, Cotopaxi, Antisana), or the floor of the great depression between.
On Cotopaxi, at elevations of 13,000 to 15,800 ft., 18 species of the genus Colpodes were collected, of which 16 were new.
Cotopaxi is only 25 m.
From the west it receives a secondary tributary, the Curaray, from the Andean slopes, between Cotopaxi and the volcano of Tunguragua.
Chimborazo, which is not in the main chain, reaches 20,517 ft.; Cotopaxi (19,580), Antisana (19,260), Coyambo (19,200) are in the eastern range, with many other peaks over 16,000 ft.