The green scum which forms on still water in this country is of vegetable origin--confervæ. When the rains fall they swell the lagoons, and the scum is swept into the Lake; here it is borne along by the current from south to north, and arranged in long lines, which bend from side to side as the water flows, but always N.N.W. or N.N.E., and not driven, as here, by the winds, as plants floating above the level of the water would be. _7th June, 1869._--It is remarkable that all the Ujiji Arabs who have any opinion on the subject, believe that all the water in the north, and all the water in the south, too, flows into Tanganyika, but where it then goes they have no conjecture. They assert, as a matter of fact, that Tanganyika, Usigé water, and Loanda, are one and the same piece of river. Thani, on being applied to for men and a canoe to take me down this line of drainage, consented, but let me know that his people would go no further than Uvira, and then return. He subsequently said Usigé, but I wished to know what I was to do when left at the very point where I should be most in need. He replied, in his silly way, "My people are afraid; they won't go further; get country people," &c. Moenegheré sent men to Loanda to force a passage through, but his people were repulsed and twenty killed. Three men came yesterday from Mokamba, the greatest chief in Usigé, with four tusks as a present to his friend Moenegheré, and asking for canoes to be sent down to the end of Urundi country to bring butter and other things, which the three men could not bring: this seems an opening, for Mokamba being Moenegheré's friend I shall prefer paying Moenegheré for a canoe to being dependent on Thani's skulkers. If the way beyond Mokamba is blocked up by the fatal skirmish referred to, I can go from Mokamba to Rumanyika, three or four or more days distant, and get guides from him to lead me back to the main river beyond Loanda, and by this plan only three days of the stream will be passed over unvisited. Thani would evidently like to receive the payment, but without securing to me the object for which I pay. He is a poor thing, a slaveling: Syed Majid, Sheikh Suleiman, and Korojé, have all written to him, urging an assisting deportment in vain: I never see him but he begs something, and gives nothing, I suppose he expects me to beg from him. I shall be guided by Moenegheré. I cannot find anyone who knows where the outflow of the unvisited Lake S.W. of this goes; some think that it goes to the Western Ocean, or, I should say, the Congo. Mohamad Bogharib goes in a month to Manyuema, but if matters turn out as I wish, I may explore this Tanganyika line first. One who has been in Manyuema three times, and was of the first party that ever went there, says that the Manyuema are not cannibals, but a tribe west of them eats some parts of the bodies of those slain in war. Some people south of Moenékuss[5], chief of Manyuema, build strong clay houses.