YAOS, or AJAWA  , a Bantu-Negroid people of east-central Africa, whose home is the country 'around the upper reaches of the Rovuml river, and the north of Portuguese East Africa . They are an enterprising and intelligent race, and have spread into British territory south of Lake Nyasa and throughout the Shire districts . They are the tallest and strongest of the natives in the Mozambique country, have negroid features and faces which are noticeable for their roundness, and, for Africans, have light skins . They have long been popular among Europeans as carriers and servants . They earned, however, a bad name as slave-traders, and gave much trouble to the British authorities in Nyasaland until 1896, when they were reduced to submission . They do not tattoo except for tribal marks on their foreheads . The women wear disks of ivory or burnished lead in the sides of their nostrils, and some, probably of Anyanja origin, disfigure the lip with the pelele or lip-ring . The Yaos have elaborate ceremonies of initiation for the youth of both sexes . They bury their dead in a contracted position, the grave being roofed with logs and earth sprinkled over; in the case of a rich man, some of his property is buried with him and the rest is inherited by his eldest sister's son . See Miss A . Werner, The Natives of British Central Africa (1906); Sir H . H .

Johnston, British Central Africa (1897); H . L . Duff, Nyasaland under the Foreign Office (1903) . For the Yao language see BANTU LANGUAGES . YA'QUBI [Ahmad ibn abi Ya'qub ibn Ja'far ibn Wahb ibn Wadih] (9th century), Arab historian and geographer, was a great-grandson of Wa41ih, the freedman of the caliph Mansur . Until 873 he lived in Armenia and Khorasan; then he travelled in India, Egypt and the Maghrib, where he died in 891 . His history is divided into two parts . In the first he gives a comprehensive account of the pre-Mahommedan and non-Mahommedan peoples, especially of their religion and literature . For the time of the patriarchs his source is now seen to be the Syriac work published by C . Bezold as Die SchatzhOhle . In his account of India he is the first to give an account of the stories of Kalila and Dimna, and of Sindibad (Sinbad) . When treating of Greece he gives many extracts from the philosophers (cf .

M . Klamroth in the Zeitschrift der deutsclzen morgenlandischen Gesellschaft, vols. xl. and x1i.) . The second

part contains Mahommedan history up to 872, and is neither extreme nor unfair, although he inherited Shi'ite leanings from his great-grandfather . The work is characterized by its detailed account of some provinces, such as Armenia and Khorasan, by its astronomical details and its quotations from religious authorities rather than poets . Edition by T . Houtsma (2 vols., Leiden, 1883) . Ya'qubi's geography, the Kitdb ul-Buldan, contains a description of the Maghrib, with a full account of the larger cities and much topographical and political information (ed . M. de Goeje, Leiden, 1892) . (G . W .