EXPLOUATION OF TWAT. 45| in the winds or mountain Ror^«. But in ordinary language, tho terra Twut, which in Berber means "the ()a«eM," is applied collectively to all the palm grovM 8cattere<l over tho desert lK»tvcH>n the Tuareg country and the region of tho great western dunes. The Ourara district, round the north side of which thene MmdhilU develop a vast amphitheatre, thus forms part of Twat.as does uUt the strip of hind supplied with moisture by the underground waters of the Sauru between Karza« and Taurirt. Lastly, the Tidikelt oases, constituting the most extensive group of cultivated territory in the whole region, is include in the same country of Twat It may be statotl in a general way that Twat comprises the wh«»le region of Quaternary alluvia which sweeps in crescent form round tho west and south aides of the extensive cretaceous Tadomait plateau. Its natural limits on the north sidoar« formefl by the dunes of the Western Erg ; on the west, Ix'yond the Wwl Saura, by the Iguidi sands ; on the south by the Devonian plateau of Muidir. The plains thus limited are, however, divided into isolated cultivable tracts by intervening stony hamadas and ranges of sandhills. Exploration op Twat. The conimercial relations are so frequent between Mauritania and Twat, the natural centre of trade of the western Sahara, that the fullest dttails reganling this region have easily been obtained through the reports of the native traders. But hitherto very few European travellers have j)enetrattHl to these isolated Mussulman communities. Under the escort of the Ifogha Sheikh Othtnan, Laing visited Twat in the year 1S'2C, at a time when its inhabitants had not yet any grounds for fearing that their territory might possibly be occupied by any Euroj)ean Power. In l^<t)l the French officers Colonieu and Burin, while traversing the zone of great dunes south of the province of Oran, entered the Ourara district. But all farther advance in this direction was barred, and they were comi)elled to retrace their steps north* wards without accomplishing their mission. Gerhard Bohlfs was somewhat more successful, having managed in IS(>4 to spend over a month in tho Twat oases, disguistnl, however, as a Mussulman, and envoy of the Sherif of Wezzan. He had also taken the pn-caution of giving himself an iilustriou's gonealopy, tracing his descent back to the royal race of the Aba.ssides. The faithful accordingly assembled to kiss the hem of his garment, and spread abroad the fame of his miraculous cures. He was even rejKjrted to have restored their sight to the blind. Ten years afterwards, M Soleillct, coming from the north, also presented himself Ix^fore Insalah : but In-ing neither one of the Abassides, nor yet a follower of the Prophet, he sought in vain for i)ennission to enter the oases, and was fain to return with his four companions to El-Golea. Three Roman Catholic missionaries, who followed the same route in the year 1876, were murdere<l on the way, before getting so far as Twat. Apart from the hostility of the natives, the route itself presents but few physical difficulties. From El-Golea to Timimun in the Gurura district, the traveller need but follow the beaten track between the region of great dunea and the western
