The knowledge of the coastal district was extremely limited. Burton and Mann had ascended the Cameroon mountains in 1861-62. In 1872-75 three German scientists, Buchholz, Reichenow and Lüders, made important zoological discoveries, while Rogozinsky, a Pole, in 1883, reached as far as Lake Barombi. But all efforts to penetrate into the interior were frustrated by the impracticable condition of the roads, the unhealthiness of the coast district--which was for the greater part uninhabited virgin forest--and by the hostile attitude of the natives. After many fruitless endeavours to explore this coastal region, an expedition in 1888 succeeded in crossing from Batanga by way of Njong and Sanaga, and in settling the boundary between Bantio and Sudannegern. The effort to reach the Cameroon estuary was frustrated by the opposition of the Bakoko; and after a journey of much difficulty the expedition returned to the coast. In 1899 a station was established and a foothold secured. In the same year the region north of Duala was explored, and the forest district traversed, the plateau of Baliland was ascended, and the grassy lands reached. With indescribable difficulty the districts from Ibi on the Benue to Yola were traversed. In 1902-4 an Anglo-German expedition, after a very minute survey, fixed the boundary line between Yola and Lake Chad, and in 1908 an agreement was made between Germany and France regarding the south and east boundaries. In 1907-8 the frontier between Cameroon and the Nigerias was surveyed by the British and German representatives, and the approximate line of demarcation subsequently settled between the two Governments was fixed and marked by an Anglo-German commission in 1912-13. BOUNDARIES AND TOWNS. The Cameroons are bounded on the north-west by Nigeria, on the north-east and east by the French possessions of the Military Territory of Chad and the Middle Congo and the French possession of Gaboon. The frontier runs in a north-easterly direction from near Calabar in the Southern Provinces of Nigeria to Lake Chad, and then in a general south-south-east direction to about lat. 2° N., from whence it strikes south-west by west, reaching the Atlantic just south of Spanish Guinea, which is thus surrounded on the north, east and south by German territory. The general outline of the country thus described is broken in the middle east by a triangular piece of land which gives access to the Ubangi river, an affluent of the Congo, at Singa, in lat. 3° 40´ N.; whilst in the south-east corner a strip of land seventy miles broad runs southwards, giving access to the Congo itself in about lat. 1° S. The Protectorate, with an area of 290 square miles, had in 1913 an estimated native population of 2,650,000, and a European population of 1,871, of whom 1,643 were Germans.