The docks are busy places, for steamers from all parts of the world, and flying many flags, come here. Men of all shades, from a dirty yellow to black and white, are busy handling the staple commodity of rubber. The rubber is all put up in sacks, and taken to the shipping houses, of which there are scores near the wharves. Every one handles “caoutchouc” and the air smells of it, the hot sun giving it an odour of burnt rubber. Everywhere they are cutting the dried rubber, which looks like great cheeses, chopping it, packing it, carrying it and loading it on vessels. The Amazon district dominates the rubber market of the world. Pará and Manaos are the greatest rubber exporting ports of that district. From these cities the rubber buyers make their expeditions into the very heart of the Amazon, and its many tributaries are nearly all the home of rubber gatherers. From these centres the Indian gatherers make their expeditions by canoe, and through almost trackless forests to the trees which they are tapping. These trees do not grow in clumps, but one will be found here, another there, and oftentimes these single trees are at a distance of several hundred yards from each other. The amount of crude rubber that the native can gather depends on how close the trees may be to each other. Upwards of one hundred rubber-bearing trees, vines and shrubs have been classified; but the one known as the _Hevea_ is the rubber tree _par excellence_ of Brazil. It is indigenous to the Amazon and its tributaries. Trees are oftentimes found which are as much as twelve feet in circumference, but those are exceptional. They require an abundance of moisture, and it is only in the thick forest, where the necessary moisture is constant and abundant, that they will reach this extraordinary size, although the trees can be successfully cultivated. It is quite probable that thousands of these trees are still undiscovered, and perhaps large districts still await development; but it is equally certain that the rubber prospector has threaded his way through thousands of miles of Amazonian jungle in his search after this profitable article of commerce. The present unprecedented prices have bestirred the exporting firms to feverish activity. Sections of hitherto unpierced forest are now being treaded by the prospector, with his Indian guides busily engaged in cutting a path through the dense undergrowth and labyrinth of vines. The howling of the enraged beasts thus disturbed in their lairs, the fear of poisonous snakes, the dread of the fever-laden mosquito, the annoyance of troublesome insects are nothing, with the price of rubber soaring upwards towards three dollars per pound.