Higher up the forests begin, and, as far as is known, the upper valley of the Caura is all forest, with very few savannahs. In these forests the tonka-bean (_sarrapia_) grows to perfection, and the collecting of these, and of a certain amount of copaiba-balsam and cedar-wood, constitutes the chief industry of the Caura settlements. Of late years the tonka-bean has gone down in value, and the inhabitants have turned their attention more to rice-farming, for which the Caura lowlands are well fitted. Most of the produce is used locally, but a small surplus is shipped to Ciudad Bolivar. The dense forests are not absolutely unbroken, however, for here and there are bare open spaces of flat granite rock, known as _lajas_; it is to these that the foresters come often to crush and dry the tonka-beans. Up the Nichare, a western tributary of the Caura above the Raudales of Mura, there is said to be much rubber of good quality, but it remains practically untouched for want of population in the region. Some 130 miles up the Caura from its mouth are the falls or rapids of Pará, with a total descent of apparently about 200 feet, according to André, the author of the only reliable account of the Upper Caura. Some day, as he suggests, the falls may provide power for saw-mills and a town whose prosperity is founded upon the natural wealth of the surrounding forest; at present all is wild, and almost unknown. There is a portage over the falls, by way of an island in the middle, and then begins the Merevari, as the Caura above Pará is called. The two chief tributaries on the west bank are the Nichare, already mentioned, and the Erewato, above Pará, once colonised by the early missionaries and afterwards the line of a short cut to the Upper Orinoco; now the valley is unknown to Europeans. Two days’ journey in canoes above the big rapids is the gorge of Ayaima, where the great stream is forced to rush through a channel 30 feet wide, between walls of granite. Above this the flat-topped, steep-sided peak of Achaba, and beyond it those of Arichi to the west and Améha to the east, may be seen. On his adventurous journey André reached the last of these, where he experienced one of the severe thunderstorms of the region, interpreted by the Waiomgomos as the angry voice of the spirits of the mountain. These Waiomgomos are found in their original haunts round the head-waters of the Caura, and there they are said to go about with faces and bodies painted bright red, wearing only the _guayuco_ or _buja_. It is strange that they are very reluctant to give their Indian names to outsiders, and always on approaching the bounds of civilisation adopt a Spanish name. The forests and savannahs of the Lower Caura, like most of the districts near the Orinoco, are frightfully infested with bush-ticks, mosquitoes, and sandflies; higher in the hills these pests decrease, but they effectually prevent absolute enjoyment of an exploring trip where they are found.