With reference to the illustrations, I should mention that I carried a photographic apparatus with me across the Continent, and so long as my dry plates held out I never lost an opportunity of obtaining a good view, and when my plates were used up I found the reflection of the scenes on the ground glass of my camera an invaluable aid to my unpractised pencil. In conclusion, I have to thank Mr. Phil. Robinson, the author of ‘In my Indian Garden,’ for assisting me in the revision of my work. My acknowledgments are also due to Lieut. S. Schofield Sugden, R.N., for the perseverance and enthusiasm with which he recalculated all my observations, making even the irksome compilations of maps a pleasant task. In their drawing and engraving work, Mr. E. Weller and Mr. E. Stanford, and in the intelligent reproduction of my pictures, Mr. J. D. Cooper, have earned my thanks, and in no less a degree Messrs. William Clowes and Sons, for the care and despatch with which these volumes have been prepared for the public. H. M. S. LONDON, _Nov. 15, 1879_. PREFACE TO THE EDITION OF 1899. --- ‘THROUGH THE DARK CONTINENT’ was first published in June, 1878, and now that, after an interval of twenty years, another fully illustrated edition is to be issued, it has been thought desirable by the publishers that I should employ the opportunity of reviewing a few of the amazing changes that have taken place in the regions described in the book. Public speakers, I observe, when they have occasion to refer to the remarkable progress made of late years in Equatorial Africa, vaguely date it as having begun some twenty-five or thirty years ago. In reality, however, the first glimmerings of the dawn only appeared in the latter part of 1875, which was soon after the publication of my appeal for missionaries to Uganda. Although the appeal was almost immediately responded to by the Church Missionary Society, and a sum of £24,000 was collected, the missionaries did not leave England until April, 1876, and it was the 30th June, 1877, before two of the band landed in Uganda. These two pioneer missionaries, and a third, who had been left behind at the south end of Lake Victoria, were, with myself, the sole Europeans in all Equatorial Africa on that date. I happened to be then about two hundred miles from the west coast, laboriously working my way down the cataracts of the Congo, to put the finishing touch to my exploration of the course of that river, while over two thousand miles eastward of me my two fellow-countrymen were preparing for the great work of converting Uganda to Christianity.