To engage in the importation of slaves it was necessary first to obtain a royal license, a privilege jealously guarded, and seldom if ever granted to Spain's ancient rivals, the Portuguese, but freely bestowed on the English, who gradually monopolized the trade. So great were the profits that Portuguese and English alike were found continually violating the law and setting the king at defiance.[XXII‑6] The regulations embraced also their intercourse with Indians, so as to discourage as much as possible their association with lawless bands, dangerous to Spanish security, and prejudicial to peaceable natives; for, with the presumption so common among lower races and classes, the negro failed not to take advantage of any privilege he might obtain over his red-skinned neighbor.[XXII‑7] Such checks proved of little use, however, since they also applied in part at least to Spanish task-masters. Indeed, in a royal cédula issued in 1593, attention is called to the fact that no one had been brought to justice for any of the extortions or cruelties to which the Indians had been subjected.[XXII‑8] Other stringent laws were issued, but they came too late, or were neglected like the rest. Under the yoke of their various oppressors the native population of the Isthmus gradually disappeared, and toward the close of the century their numbers had become insignificant. * * * * * In the affairs of Panamá, we enter now an era of decline. Progress hitherto on the Isthmus has been on no permanent basis. For a time the gold and pearls of seaboard and islands kept alive the spirit of speculation, which was swollen to greater dimensions by the inflowing treasures from Peru and Chile, and from scores of other places in South and North America. When these began to diminish, commerce fell off, and as it had little else to depend upon there was necessarily a reaction. Panamá had comparatively but little indigenous wealth and was largely dependent for prosperity on Spain's colonial policy. Unfortunately this was characterized by a short-sightedness which eventually proved disastrous both to the province and the empire. The great fleets which arrived from Spain came in reduced numbers, at longer intervals, and with depleted stores. In 1589, ninety-four vessels reached the Isthmus laden with merchandise; sixteen years later the fleet mustered only seventeen ships.[XXII‑9] To the depredations of buccaneers which will be hereafter described this state of affairs may in part be attributed, but other causes were at work. The king of Spain had already appeared before his subjects at Panamá in the character of a royal mendicant;[XXII‑10] and now he laid restrictions on their trade which could not fail to prove disastrous to the commercial interests of the city. [Sidenote: ASIATIC TRADE.]