172 THE UPPER AMAZONS. Chap. III. 



dread of the " terras cahidas," or landslips, which occa- 

 sionally take place along the steep, earthy banks ; espe- 

 cially when the waters are rising. Large vessels are 

 sometimes overwhelmed by these avalanches of earth 

 and trees. I should have thought the accounts of them 

 exaggerated if I had not had an opportunity during this 

 voyage of seeing one on a large scale. One morning I 

 was awoke before sunrise by an unusual sound resem- 

 bling the roar of artillery. I was lying alone on the top 

 of the cabin ; it was very dark, and all my companions 

 were asleep, so I lay listening. The sounds came from 

 a considerable distance, and the crash which had aroused 

 me was succeeded by others much less formidable. The 

 first explanation which occurred to me was that it was 

 an earthquake ; for, although the night was breathlessly 

 calm, the broad river was much agitated and the vessel 

 rolled heavily. Soon after, another loud explosion took 

 place, apparently much nearer than the former one ; 

 then followed others. The thundering peal rolled back- 

 wards and forwards, now seeming close at hand, now far 

 off ; the sudden crashes being often succeeded by a pause 

 or a long-continued dull rumbling. At the second 

 explosion, Vicente, who lay snoring by the helm, awoke 

 and told me it was a " terra cahida ; " but I could 

 scarcely believe him. The day dawned after the uproar 

 had lasted about an hour, and we then saw the work of 

 destruction going forward on the other side of the river, 

 about three miles off. Large masses of forest, including 

 trees of colossal size, probably 200 feet in height, were 

 rocking to and fro, and falling headlong one after the 

 other into the water. After each avalanche the wave 



