The explorer who penetrated into the forest in search of seringaes, examined the banks of the river by which he went up and when he verified the existence of a favorable zone, he landed and after a careful exploration under the direction of specialist-workmen called “matteiros” (foresters) he settled down and gave himself up to the exploitation of the “seringal” he selected. That occupation of virgin ground and its being made use of constituted the act of possession, the first step towards acquiring the property. In order to definitely assure the dominion of the lands selected, it became necessary to obtain a title of ownership from the Government of the State in which these lands were located, this being drawn up only after that the respective marking out and survey by an authorized engineer or surveyor, the depositing of the respective plans, the verification that no anterior rights or claims existed on the part of third parties, as also the payment of the respective taxes being satisfied, which last averaged about 5$000 per hectare. Only after that all these formalities had been complied with, was the concession granted definitely, and the possession considered as complete. The title deeds of the property with the respective specifications is registered in special blocks, which will serve as proof in case of future dispute and will furnish authentic documents in place of the property-titles that may have been mislaid or lost. Once the concession is legalized and the possession marked out, the property rights are considered irrefutable. The dominion of the lands being assured, their usefulness will depend upon the co-existence of two essential factors—labor and capital. In the regions of the Amazonian valley, sparingly peopled by the want of direct immigration, the work is done by the natives and principally by Cearenses, people from Ceará. Under the general designation of =Cearenses= are comprised the populations of the northeast of the country from Bahia to Piauhy, a strong race endowed with rare energy. Having immigrated from their native state fleeing from privations to which the periodical dry seasons reduce them, they arrive completely without the means of subsistence, it being necessary for the owners of the “seringas” who contract their services to take measures for their transport, alimentation and maintenance in the seringaes until with the delivery of the rubber collected, they find themselves in a position to liquidate the debts that they have contracted and the expenses that have been occasioned. On the other hand in their turn the owners of seringaes not disposing of capital are placed under the necessity of raising loans with which to defray the exploitation of their lands. These resources are furnished them by the traders, part in money and part in merchandise, these traders being known as =aviadores= whilst the proprietors are called patrons or aviados.