LIFE IN TEFF& 249 



tbo /ate of about a foot a day. It was easy to measure its 

 retreat by the effect of the occasional rains on the beach. 

 The shower of one day, for instance, would gully the sand 

 to the water's edge, and the next day we would find the water 

 about a foot below the terminus of all the cracks and ruts 

 thus caused, their abrupt close showing the line at which 

 they met the water the previous day. Ten days or a fort- 

 night before we left, and during which we had heavy 

 rains at the close of every day, continuing frequently 

 through the night, those oscillations in the river began, 

 which the people here call " repiquete," and which, on 

 the Upper Amazons, precede the regular rise of the water 

 during the winter. The first repiquete occurs in Teff 

 toward the end - of October, accompanied by almost daily 

 rains. After a week or so the water falls again ; in ten 

 or twelve days it begins once more to ascend, and sinks 

 again after the same period. In some seasons there is a 

 third rise and fall, but usually the third repiquete begins 

 the permanent annual rise of the river. On board the 

 steamer we were joined by Mr. Bourget, with his fine 

 collections from Tabatinga. He, like both the other par- 

 ties, has been hindered, by want of alcohol, from making 

 as large collections as he might otherwise have done ; but 

 they are, nevertheless, very valuable, exceedingly well put 

 up, and embracing a great variety of species, from the 

 Marafion as well as from the Hyavary. Thus we have a 

 rich harvest from all the principal tributaries of the Upper 

 Amazons, within the borders of Brazil, above the Rio Negro, 

 except the Purus, which must be left unexplored for want 

 of time and a sufficient working force. 



On leaving Teff I should say something of the nature 



of the soil in connection with Mr. Agassiz's previous 



11* 



