While in Liberia, I have traversed rivers in an open boat at night, slept beyond the Kavalla Falls in open native houses, and at the residence of Rev. Alexander Crummel, Mount Vaughan, Cape Palmas, I slept every evening while there with both window and door as ventilators. The window was out and the door inside. In Abbeokuta, Ijaye, Oyo, and Ogbomoso, we slept every night with ventilated doors and windows, when we slept at all in a house. But in Illorin we always slept out of doors by preference, and only retired to repose in-doors (which were always open) when it was too cool to sleep out, as our bedding consisted only of a native mat on the ground, and a calico sheet spread over us. And I should here make acknowledgments to my young colleague, Mr. Campbell, for the use of his large Scotch shawl when I was unwell, and indeed almost during our entire travel--it being to me a great accommodation, a comfort and convenience which I did not possess. Test of Exposure I have started two and three hours before daybreak, laying on my bed in an open canoe, ascending the Ogun river, at different times during the six days' journey up to Abbeokuta; Mr. Campbell and myself have frequently slept out in open courts and public market-places, without shed or piazza covering; and when journeying from Oyo to Ibaddan, for three successive evenings I lay in the midst of a wilderness or forest, on a single native mat without covering, the entire night; and many times during our travels we arose at midnight to commence our journey, and neither of us ever experienced any serious inconvenience from it. Improved Window and Door Ventilation That houses in Africa may be properly ventilated during the night without annoyance, or, what is equally as bad, if not worse, the continual fear and imagination of the approach of venomous insects, creeping things, and reptiles, the residents should adapt them to the place and circumstances, without that rigid imitation of European and American order of building. Every house should be well ventilated with windows on opposite sides of the rooms, when and wherever this is practicable, and the same may be said of doors. And where the room will not admit of opposite windows, or windows at least on two sides of a room, whether opposite or otherwise, a chimney or ventilating flue should be constructed on the opposite side to the window--which window should always be to the windward, so as to have a continual draught or current of fresh air. Persons, however, should always avoid sitting in a _draught_, though a free circulation of air should be allowed in each room of every house.