Soon it was clear that the delta of the river had been reached. From being a united volume of water it began to break up into numerous branches, running in all directions. At the apex of the delta the land was dry, and clad with palm oil groves and silk cotton trees. Gradually, however, these disappeared, and as the dry land gave place to hybrid swamp, the mangrove asserted its ownership. Nature then showed as repulsive an aspect as is to be met with in any other region on the face of the globe--what was swamp when the tide was out resembling a submerged forest when the tide was in, and both then and at all other times, reeking with pestilential vapours from the slimy mud oozing from between the octopus-like roots of the mangrove. [Illustration: AKASSA.] In passing through this foul region the travellers had little reason to wonder that no one had ever ventured to explore the labyrinthine creeks and river branches which penetrated the mangrove in all directions, but seemed to lead to nowhere in particular. On the 24th November 1830 the dull thunder of the Atlantic rollers breaking on the shore came like sweetest music to the travellers’ ears, growling a gruff but hearty welcome, and soon the sea itself lay before them--its cool healthy breezes fanning them with delicious touch, its gleaming limitless expanse fair as a glimpse of heaven. The Niger mystery was solved at last, and the river portals thrown wide open to the world, never again to be closed. CHAPTER XXVIII. _FILLING UP THE DETAILS._ While Clapperton and Lander were thus bringing the work of Park to a successful conclusion, and proving the accuracy of M‘Queen’s geography of the Niger basin, there were others at work in the region which the labours and death of their great pioneer had made classic ground. Major Laing, in the course of a Government mission, had travelled from Sierra Leone to Falaba, in the country of Sulima, and ascertained that the Niger took its rise in the Highlands of Kurauka, some 70 miles south-west of Falaba, and not more than 150 miles east of Sierra Leone. The river itself he was prevented from reaching, but none the less did he come under the irresistible influence of its fascination. More than ever had Timbuktu and the Niger become names to conjure with, as well as to infect men with a species of reckless self-sacrifice that no amount of past experience, prudence, or common sense could dispel. As in the case of Lander, and others of his predecessors, having once tasted the bitter-sweet of African exploration, there could be no rest for Major Laing until he had gathered again the magic fruit. Accordingly, after an interval of three years, he once more set forth, determined to carry his cherished dreams into realisation.