SONGHAY UNDER ASKIA THE GREAT 197 By the acquisition of the Haussa States the territory of the empire was carried from Bornu on the borders of Lake Chad to the Atlantic. The southern limits had been securely extended, by the final conquest and conversion of Mossi and the subjection of Borgu, to the mountains which divide the uplands of the interior from the jungle of the coast. Its northern frontier was reestablished on the old limits of the Mellestine, being so far enlarged in the north-east by the conquest of Aghadez as to command the Tripoli- Fezzan route into the desert.

It already commanded the routes entering on the west from Sidjilmessa and Wargelan. Thus Songhay held the southern side of the three already mentioned "gates of the desert," and in language of latitude and longitude the empire may be described as extending, in the middle of the sixteenth century, from about 17° west to 13° east, and from about 10° to between 25° and 30° north. Its shape, however, was not that of a parallelogram, but rather that of a figure enclosed within a great semicircle, of which the base, extending from the country south of Lake Chad to the Atlantic, measured about 2000 miles, while the greatest diameter, taken at right angles to the base due north in the neighbourhood of Twat, measured a little over 1000 miles.

For the purposes of administration this vast empire was divided into the home provinces and the viceroyalties. There were four vice-royalties. Beginning at the west, the first vice-royalty was called Kormina, and was composed of the south-western provinces, including what remained of the dismembered Melle, the Fulani State of Masina, the country of the pagan Bambaras, and the territory lying between the Niger and the Atlantic, up to the limit at which it met the frontier line of the second vice-royalty known as Bal or Bala. The vice-royalty of Bal took in the northwestern provinces, including Ghanata, and extended from Timbuctoo to the salt-mines of Tegazza. The frontier of Bal was conterminous in the desert with the frontier