Nor was permanency of settlement encouraged by the Dutch authorities. From 1705 to 1770 the Government issued what were termed "loan leases," or licenses to occupy land in the interior for grazing purposes upon the payment of a small rental and with a right to re-assume possession at any time retained by the Government. Combined with changes in the seasons and the pasturage, and the desire to obtain better locations, this system encouraged the formation of that peculiar characteristic called "trekking," which has marked the pages of South African history with so much bloodshed and trouble. It also brought the wandering farmers, or Boers, into contact or conflict with the wandering natives. Even the Dutch officials at Swellendam and Stellenbosch complained at last of a plan under which the farmers "did not scruple to wander about hither and thither several days' journey from their loan farms;" and finally, in 1770, the system was abolished. Meantime a region larger than the British Isles had been taken from the Hottentots and their cattle driven away from the best grass-land available for their use, and which had been theirs for centuries. The natural result of cattle-stealing which ensued upon the part of the natives was punishment by the Colonists in the form of war; in the holding of captured children as apprentices or slaves; and in the occasional application of torture to individual savages. [Sidenote: Successive Racial Importations] This matter of relations with the natives and of slavery was complicated at an early date (1658) by the introduction of some negro slaves from a Portuguese ship. They were brought from the coast of Guinea and sold to the Government for rough labor in the neighborhood of Cape Town, and also to some of the more distant settlers. Naturally inclined, already, to utilize natives for any work of a manual nature, this official encouragement immediately complicated the relations between Hottentots and Bushmen and the Dutch farmers. The latter, having once tasted the pleasures of slave-ownership in the midst of vast reserves of dark-skinned people, soon put the principle into the fullest practice and application. From time to time further consignments of slaves from other parts of Africa were introduced by those inveterate dealers, the Portuguese, and to them were soon added large numbers of native criminals from Malacca, Java and the Spice Islands, who were sent by the Batavian Government to serve out terms of punishment or slavery at the Cape. They were, of course, more intelligent than the imported slaves from Guinea and Mozambique, and often made excellent masons, harness-makers, coopers and tailors; but their influence upon the moral tone of the white community amongst whom they were placed is not hard to estimate. From their arrival dates one of the many mixed races with which South Africa swarms. Another class of imported Asiatics of a higher type consisted of political offenders sent from Java