This house was a palace to the rude shanty which the seringero, or gatherer of the rubber, erects for a temporary shelter near the scene of his labors.
The owner of the house told me that the season for gathering the rubber, or seringa, as it is here called, was from July to January. The tree gives equally well at all times; but the work cannot be prosecuted when the river is full, as the whole country is then under water. Some, however, is made at this time, for I saw a quantity of it in this man's house, which was evidently freshly made.
The process of making it is as follows: A longitudinal gash is made in the bark of the tree with a very narrow hatchet or tomahawk; a wedge of wood is inserted to keep the gash open, and a small clay cup is stuck to the tree beneath the gash. The cups may be stuck as close together as possible around the tree. In four or five hours the milk has ceased to run, and each wound has given from three to five tablespoonfuls. The gatherer then collects it from the cups, takes it to his rancho, pours it into an earthen vessel, and commences the operation of forming it into shapes and smoking it. This must be done at once, as the milk soon coagulates.
A fire is made on the ground of the seed of nuts of a palm-tree, of which there are two kinds: one called urucari, the size of a pigeon's egg, though longer; and the other inajá, which is smaller. An earthen pot, with the bottom knocked out, is placed, mouth down, over the fire, and a strong pungent smoke from the burning seeds comes up through the aperture in the bottom of the inverted pot.
The maker of the rubber now takes his last, if he is making shoes, or his mould, which is fastened to the end of a stick; pours the milk over it with a cup, and passes it slowly several times through the smoke until it is dry. He then pours on the other coats until he has the required thickness; smoking each coating until it is dry.
Moulds are made either of clay or wood; if of wood, it is smeared with clay, to prevent the adhesion of the milk. When the rubber has the required thickness, the moulds are either cut out or washed out.
Smoking changes the color of the rubber very little. After it is prepared, it is nearly as white as milk, and gets its color from age.
The most common form of the India-rubber of commerce is that of a thick bottle; though it is also frequently made in thick sheets, by pouring the milk over a wooden mould, shaped like a spade, and, when it has a coating sufficiently thick, passing a knife around three sides of it, and taking out the mould. I should think this the least troublesome form, and the most convenient for transportation.
From twenty to forty coats make a pair of shoes. The soles and heels are, of course, given more coats than the body of the shoe. The figures on the shoes are made by tracing them on the rubber whilst soft with a coarse needle or bit of wire. This is done in two days after the coating. In a week the shoes are taken from the last. The coating occupies about twenty-five minutes.
An industrious man is able to make sixteen pounds of rubber a day; but the collectors are not industrious. I heard a gentleman in Pará say that they rarely average more than three or four pounds.