The spot they chose was under some lofty trees covered with climbing plants, where previous visitors had removed enough of the undergrowth to render the place suitable for a temporary camp. A fire was kindled, and over it they placed a pot for the concoction of a porridge of meat and mandioca flour mingled with water. A hammock was stretched between two of the trees, and a large fish that had been caught early in the morning was hung up by way of ornament. While the soup was in preparation, one of the men busied himself with pounding a piece of bast, or the inner bark of a tree, with a wooden hammer. Much of the clothing of the Amazonian Indians is made in this way; the material resembles the famous tappa-cloth of the South Sea Islands, and though not very serviceable, it has the merit of great cheapness. The breakfast, when ready, was distributed by the _capitano_ or first mate, who served each man in turn. It was devoured with a good appetite, and in a little while the crew was ready to resume the journey. The travellers amused themselves by studying the peculiarities of the forest, and took their own breakfast while the boat was floating down the stream. "If all goes well," said the Doctor, "we shall not be long in reaching the junction with the Madeira, and the falls of that stream." "Then we have some falls to pass, have we?" Frank asked. "Yes," replied the Doctor, "and they are a serious hinderance to navigation. In descending we can 'shoot' some of them, though not all; but if we were ascending the river it would be different. The boats must be dragged around the falls, or their cargoes unloaded and transported to other boats beyond the falls. "The Madeira drains an area of forty thousand square leagues," he continued, "and but for the falls would furnish water communication to the very heart of Bolivia. It is the natural waterway of the country, and its upper affluents traverse the richest agricultural region of South America. They have been partially but not wholly explored, and the actual number of miles open to steamboats is not yet known. "There are nineteen falls and rapids, having a descent of nearly three hundred feet altogether. They are scattered along a distance of two hundred and thirty miles. Above and below there are no impediments to navigation, with a single exception in the shape of a rapid, which may be passed by a steamboat when the river is high. "The governments of Bolivia and Brazil have endeavored to overcome these falls by building a canal or a railway around them, and spent considerable money in the preliminary work. It was found that a canal would cost a great deal of money, far more than a railway, and so it was decided to build the latter." "Did they build it?"