Rise of the Gkeat Rivek. 275 



shady dells are transformed into navigable creeks.* Swarms 

 of turtles leave the river for the inland lakes ; flocks of 

 wading birds migrate to the banks of the Negro and Ori- 

 noco to enjoy the cloudless sky of the dry season ; alliga- 

 tors swim where a short time before the jaguar lay in wait 

 for the tapir ; and the natives, unable to fish, huddle in 

 their villages to spend the " winter of their discontent." 

 The Lower Amazon is at its minimum in September or Oc- 

 tober. The rise above this lowest level is between seven 

 and eight fathoms. If we consider the average width of 

 the Amazon two miles, we shall have a surface of at least 

 five thousand square miles raised fifty feet by the inunda- 

 tion. An extraordinary freshet is expected every sixth 

 year. 



The Atlantic tide is perceptible at Obidos, four hundred 

 and fifty miles above Para, and Bates observed it up the 

 Tapajos, five hundred and thirty miles distant. The tide, 

 however, does not flow up ; there is only a rising and fall 

 ing of the waters — the momentary check of the great river 

 in its conflict with the ocean. The " bore," or piroroco, is 

 a colossal wave at spring tide, rising suddenly along the 

 whole width of the Amazon to a height of twelve or fifteen 

 feet, and then collapsing with a frightful roar. 



The Amazon presents an unparalleled extent of water 

 communication. So many and far reaching are its tribu- 

 taries, it touches every country on the continent except 

 Chile and Patagonia. South America is well nigh quar- 

 tered by its river system : the Amazon starts within sixty 

 miles of the Pacific ; the Tapajos and Madeira reach down 

 to the La Plata ; while the Negro mingles its waters with 

 those of the Orinoco. The tributaries also communicate 

 with each other by intersecting canals, so numerous that 

 central Amazonia is truly a cluster of islands. Wagons 



* The flooded lands are called gapos. 



