46 M. Boussingault's [July 



in the neighbourhood of the equator ; and I had been fortu- 

 nate enough to be able to continue my researches upon the 

 decrease of the heat in the intertropical Andes to the great 

 height of 5500 metres (17,040 feet). 



I found myself at Rio Bamba, resting myself, after my 

 recent excursions, to Cotopaxi andTunguragua. I wished to 

 contemplate at my leisure, to satiate myself, as it were, 

 with the view of the majestic glaciers, which have so often 

 attracted the attention of scientific men, and to which it 

 was necessary that I should soon bid an eternal farewell. 



Rio Bamba is, perhaps, the most singular diorama in the 

 world. The town presents nothing remarkable in itself: 

 It is placed on one of those arid plateaus so common in the 

 Andes, and which have all, at this great height, a charac- 

 teristic wintry aspect, which fills the traveller with a feeling 

 of melancholy. It is true that, in order to reach it, he 

 must traverse a most picturesque region, and it is always 

 with regret that he exchanges a tropical climate for the 

 northern frosts. From the house in which I resided I could 

 survey Capac-urcu, Tunguragua, Cubille, Carguairazo, to 

 the North Chimborazo, and several other celebrated moun- 

 tains of Paramos, which, although free from eternal snow, 

 are of high geological interest. 



This vast amphitheatre of snow, which limits on every 

 side the horizon of Rio Bamba, is a continual subject for 

 observation. It is curious to notice the appearance of these 

 glaciers at different hours of the day, to see their apparent 

 height, varying from one instant to another by the effect of 

 atmospheric refraction. With what interest does not one 

 view, in such a circumscribed space, the appearance of all 

 the great meteorological phenomena. Here may be seen 

 those immense clouds which Saussure has well defined by 

 the denomination of parasitical clouds, and are distinguished 

 by their attaching themselves to the middle of a trachyte 

 cone. There they stick, uninfluenced by the wind, which 

 blows powerfully upon them. But soon the lightning shines 

 through the midst of the mass of vapour, and hail, mixed 

 with rain, inundates the base of the mountain, while its 

 snowy summit, which the storm cannot reach, shines re- 

 splendent with the rays of the sun. At a distance there is 

 a line of ice shooting forwards, shining brilliantly like a 



