a big machete (tercado in Portuguese) in his hand and the indispensable Winchester .44 over his shoulder he enters the jungle and searches out the rubber trees. As he locates them he connects them by a trail cut through the undergrowth, and this trail connecting the rubber trees is his estrada. Estradas vary in the number of trees which they contain, from 50 to 300, depending on the conditions and the men who lay them out.

Generally a seringueiro will lay out two or three estradas extending in different directions from his dwelling, and these are afterwards tapped in rotation. After the trees in the estradas are located, some further work is necessary to clean the trails more thoroughly, to bridge streams with poles, and the like. Then the seringueiro is ready to begin tapping. Of course, if old estradas are to be worked all this is unnecessary; he has only to move into the house built by his predecessor, cut the recent growth from the estrada, and repair a few bridges.

Although a seringueiro may thus establish a collecting ground of his own at some distance from any of his fellows, it is more usual for a group of seringueiros to enter a region together and lay out estradas near each other.

Such a group of estradas on a rubber property is called a seringal. Each seringal has a barracão, or large warehouse and dwelling combined, where the agent of the man or company owning or leasing the rubber property lives. In the barracão a store of food and supplies for the seringueiros is kept. These commodities are advanced to the seringueiros as they need them and are charged against the value of the rubber which they bring to the barracão from time to time. The plan of a seringal with its estradas may be seen in Pearson's book (32, p. 63). The map of an estrada in Matto Grosso studied in detail by the writer is shown as Figure 3.

Tapping is begun by the seringueiro in the early morning. Incisions are made in the bark of the rubber tree with a small ax, called a machadinho. The purpose of these incisions is to open the latex vessels which extend through the cortex of the tree, so that the latex, or "milk," may flow out. The cuts are made in a slanting direction, so that the latex flows from the upper end of the cut to the lower, where a cup is placed to receive it. This cup is made of light-weight tin plate and is affixed to the tree by thrusting the sharp edge of the brim into the bark.

Several incisions are made at equal intervals around the tree and cups placed beneath them, when the seringueiro hurries on to the next tree. So he continues until the whole estrada is tapped. Usually he has finished tapping by 9 o'clock. Early tapping has been found to give the highest yields, as the flow of latex decreases considerably as the temperature rises, partly, perhaps, because of the effect of the heat in coagulating the rubber on the cuts and stopping the flow and partly because of the increased transpiration of the tree, which may lower the pressure in the latex tubes and so diminish the flow.

partly

When the seringueiro judges that the flow of latex has ceased, he begins to collect the contents of the cups. The latex from each cup he pours into a narrow-mouthed tin pail, called a "baldé," of about 2 gallons capacity. When the baldé is filled he pours the latex from it into a cloth bag which has been thoroughly coated with latex and smoked to coagulate the rubber on its surface, so that it is

waterproof. This bag is tied with a strong rubber band, put into a wicker supporting frame, and carried on the seringueiro's back while the baldé is refilled. Each cup as it is emptied is roughly wiped out with the fingers and hung upside down on a convenient twig, to prevent its being filled with water by the rains. Figure 2 shows a seringueiro with his collecting outfit.

When he returns with his latex the seringueiro rests for a time and eats his midday meal. Then he builds a fire in the palm-thatched hut used for smoking rubber. Usually the fire is built in a little pit

FIG. 3.-An estrada of virgin trees on the Rio Ouro Preto, Matto Grosso, Brazil. (Drawn by Avellino Olivera, of the Brazilian Commission)

under a dome or cone of baked clay which has an opening at its apex through which the smoke pours in a dense cloud. Sometimes the fire is built on the surface of the ground, and a cone of tin is inverted over it. The fruits of Attalea excelsa are much used for making the smoke to cure rubber, and for a long time the superior qualities of the fine hard Para rubber were supposed to be due to the use of this smoke. On this account the export of seeds of this tree from Brazil was forbidden by law. It is now known that other substances serve very well for smoking the rubber; fruits of the babuassu palm are used and also various types of wood.

If a ball of rubber has been started on preceding days and not yet finished the seringueiro adds to this. This ball is formed on a pole about 6 feet long, which is laid across two other poles supported at either end by posts set on either side of the smoking cone. enables the pole bearing the rubber ball to be rolled back and forth, into the smoke, then out of it.

This

The latex is poured into a pan set just back of the smoking cone. With one hand the ball of rubber is now rolled over the basin, and with the other the seringueiro dips up latex from the pan in a calabash and pours it over the ball. As soon as the latex ceases to drip the ball is rolled into the cloud of smoke and turned slowly, so that the smoke covers the whole surface of the fresh latex and coagulates the rubber in a thin film. Then the ball is again rolled over the pan, coated

FIG. 4.-A seringueiro rolling a ball of freshly coagulated rubber to shape it and press out the bubbles of air and vesicles of serum. At his right is a finished ball of fine hard Para rubber. Behind the seringueiro is the smoking shed. The rubber shoes in the foreground were made by coagulating latex over the wooden mold. The man at the right holds a cloth bag which has just been given a coating of latex

with latex, and returned to the smoke. So the process goes on until the whole of the day's collection of latex has been turned into rubber. The ball is then removed from the pole and rolled on a slab of wood to shape it and to squeeze out any liquid which has formed in it. (Fig. 4.) If the ball is large enough, about 65 kilos, it is set aside to cure; if not, it is added to on successive days until it has reached the desired size. (Fig. 5.)

A new ball is usually begun by allowing a little latex to stand in the pan over night so that it undergoes natural coagulation. The coagulum thus formed is rolled around the pole, and over this latex is poured and smoked in the manner described. This method has the advantage of quickly bringing the ball to a size such as to hold considerable latex on its surface at each pouring, but it has the disadvantage that the center of each ball is made of naturally coagulated

rubber, which is considered inferior in most markets. As the average seringueiro is not so cleanly as to care greatly what falls into the latex while it is coagulating, the coagulum usually contains various impurities.

The lumps of rubber which have formed in the latex in the cups, in transit, or in the basin are squeezed into an irregular mass, to which is added the film formed on the surfaces of the various utensils. Little attempt being made to keep this rubber clean, it is usually found to contain a considerable percentage of impurities. This low-grade rubber is called sernamby.

In some places the latex is smoked over a square paddle. The yield for one day only is smoked; then the layer of rubber is cut open at the upper end of the paddle and the paddle is pulled out.

This

FIG. 5.-Rubber awaiting shipment on the banks of the Madre de Dios, at Conquista, El Beni, Bolivia The balls are of fine hard Para rubber; the bales are of caucho rubber

leaves the rubber in a flat cake rectangular in outline. It is called knapsack rubber, presumably from the cavity in the cake formed by the paddle. At Tres Casas, on the upper Madeira River, such rubber is prepared in large quantities and is said to command the best price in Manaos (fig. 6).

Around Para, in the delta region, the rubber is much less carefully prepared. The latex is allowed to coagulate in the cups, and the rubber is then collected and pressed into irregular masses. Sometimes the latex is poured into holes in the ground to coagulate. According to Lange (15), the resulting coagulum is often allowed to stand in water for months with the idea that it will absorb water and increase in weight.

As a result of such practices this rubber comes into Para in a wet, stinking, and indescribably filthy condition, and it would likely find

no market at all were it not that a washing plant now exists in that city which washes, sheets, and dries this rubber. Considering the raw material it uses, this plant turns out a product of surprisingly good quality.

The machadinho employed in tapping usually has a cutting edge about 2.5 centimeters long, but the writer observed on the Rio Ouro Preto in Matto Grosso and elsewhere the use of machadinhos with an edge 7.5 centimeters long. In former times the machadinho was supposed to be made of iron, never of steel. Some thought this was because steel in some mysterious way injured the tree; others said that the iron ax could not be kept sharp and being dull would not penetrate to the cambium and therefore would not damage the tree. Woodroffe and Smith (48) as late as 1915 continue to perpetuate this supposition. Judging from the trees tapped in the iron age of the machadinho, one is compelled to believe that the ax rarely failed to reach the cambium.

FIG. 6.-Knapsack rubber at Tres Casas, on the Madeira River. This rubber is coagulated by smoking latex over a rectangular paddle. Each knapsack represents the collection of one man for one day

When plantation rubber first came into tapping in the East a great controversy, now merely of historical interest, arose as to the best method of tapping. Two rival schools sprang up. One insisted that the trees must be incised, as with a machadinho or other sharp instrument. The other group was for excision, that is, paring away the outer bark with a farrier's knife or a gouge, so as to open the latex vessels. The incisionists predicted the destruction of all the plantations by the arboricidal method of excision, which was not the traditional treatment to which the tree had been accustomed in its native jungles. They also expatiated on the harmlessness of the use of the machadinho and the great care with which this instrument was

used.

If there ever were seringueiros who were careful in using the machadinho the tribe has vanished from the soil-and the waters-of the Amazon area! It is hard to imagine what the incisionists thought the ever-present knots and swellings around the base of the tree might