The Insimankao concession contains 1,000 fathoms square; the measurements being taken from a 'marked tree' on the north-western slope of the hill with the long name. The position is N. lat. 5º 18' 15" and the long. W. (Gr.) 2º 14' 03". West of the centre the Fura Creek receives a small tributary. Mr. Walker took fair samples from the well-defined reef and the outcropping boulders, whose strike is from north-north-east to south-south-west. He notes that the land Egwira, which lies between Wasa and Aowin, was long famous for its mining-industry, and that it appears in old maps as a 'Republick rich in gold.' We heard of the Abenje mine on the same reef, four to five miles east of Insimankao; and he declares that it has been abandoned because the population is too scanty. I left this mining property convinced that working it will pay well. The only thing to be guarded against is overlapping the French concession of Mankuma, which lies immediately to the east. From the mine I walked back to the village, breakfasted, and returned in the canoes to the sluice-like mouth of the Fura Greek. I then ascended the Ancobra, in order to inspect the Butabue rapids, said to be the end of canoe-navigation. We passed on the right a reef and a shallow of conglomerate, washed out of the banks and forming a race; there is another reef with its rip at Aroasu. In the early part of the afternoon we got to the village of Ebiasu, which means 'not dark.' Here the equinoctial showers began to fall heavily, and I was again obliged to sleep without observations. The village is built upon a steep bank of yellow clay, with rich red oxides; it stands forty feet above the present level, and yet at times it is flooded out. Leaving Ebiasu next morning, I found the banks of sand, clay, and small pebbles beginning to shelve. We passed over slaty rocks in the bed; and the depth of water was often not more than three feet. Women's washings were seen on the left bank, and the river had risen after they had been worked. We could not approach them on account of the reefs and the current. The opposite bank, about five minutes further up, is of soft sandstone; and here a native tunnel of forty to fifty feet had been run in from the river to communicate with a shaft. My men were nervous about leopards, and I had to encourage them by firing my rifle into the hole. The normal formation continued, and here the land is evidently built by the river; there are few hills, and the present direction of the bed has been determined by the rocks and reefs, the outliers of the old true coast. These features may have been lower than they are now, and owe their present elevation to upheaval. Immature conglomerate--that is, a pudding of pebbles and hardened clay--seems to have been deposited in the synclinal curve of the bed-rock, principally slate. Overlying both are the top soil and the sands, the latter often resembling the washed out tailings of stamped rock.