The cavern was rather rough inside. When we had advanced about one hundred yards we came to a stream, or puddle of water, extending entirely across the floor, and barring our way. My men, who had gone thus far under protest, now desired to return, and urged me not to go into the water. It might be very deep; it might be full of horrible water snakes; all sorts of wild beasts might be beyond, and land snakes also. At the word snake I hesitated, for I confess to a great dread of serpents in the dark, or in a confined place, where a snake is likely to get the advantage of a man. A cold shudder ran through me at the thought that, once in the water, many snakes might come and swim round me, and perhaps twist themselves about me as they do around the branches of trees. So I paused and reflected.
While peering into the darkness beyond I thought I saw two eyes, like bright sparks or coals of fire, gleaming savagely at us. Could it be a leopard, or what? Without thinking of the consequences, I levelled my gun at the shining objects and fired. The report, for a moment, deafened us. Then came a redoubled rush of the great hideous bats. It seemed to me that millions of these animals suddenly launched out upon us from all parts of the surrounding gloom. Some of these got caught in my clothes. Our torches were extinguished in an instant, and, panic-stricken, we all made for the cavern's mouth. I had visions of enraged snakes springing after and trying to catch me. We were all glad to reach daylight once more, and nothing could have induced us to try the darkness again. I confess that, though I think it takes a good deal to frighten me, I did not at all relish remaining there in entire darkness.
The scene outside was as charming as that within was hideous. I stood a long time looking at one of the most beautiful landscapes I ever beheld in Africa. It was certainly not grand, but extremely pretty. Before me, the little stream whose fall over the cliff filled the forest with a gentle murmur, resembling very much, as I have said, when far enough off, the pattering of a shower of rain, ran along between steep banks, the trees of which seemed to meet above it. Away down the valley we could see its course, traced like a silver line over the plain, till it was lost to our sight in a denser part of the forest.
I have often thought of these caverns since I saw them, and I have regretted that I did not pay more attention to them. If I had made my camp in the vicinity, and explored them and dug in them for days, I think that I should have been amply rewarded for the trouble. At that time I did not feel greatly interested in the subject. I had not read the works of M. Boucher de Perthes and others, or heard that the bones of animals now extinct had been discovered in caverns in several parts of Europe, and that implements made of flint, such as axes, sharp-pointed arrows, etc., etc., had been found in such places. If I had excavated I might perhaps have found the remains of charcoal fires, or other things, to prove that these caverns had been made by men who lived in Africa long before the negro. I feel certain these caverns must have been human habitations. I do not see how they could have been made except by the hand of man.
On my last journey I thought once or twice of going to them from the Fernand-Vaz, to explore and dig in them. I thought I might be rewarded for labour by discovering the bones of unknown beasts, or of some remains of primitive men.
These caverns are fortunately not far away from the sea—I should think not more than ten or fifteen miles—and are situated between the Muni and the Moonda rivers. Anyone desiring to explore them would easily find the way to them. The cavern under the waterfall would be extremely interesting to explore.
The valley itself was a pleasant wooded plain, which, it seemed, the hand of man had not yet disturbed, and whence the song of birds, the chatter of monkeys, and the hum of insects came up to us, now and then, in a confusion of sounds very pleasant to the ear.
But I could not loiter long over this scene, being anxious to reach the seashore. After we set off again we found ourselves continually crossing or following elephant tracks, so we walked very cautiously, expecting every moment to find ourselves face to face with a herd.
By-and-by the country became quite flat, the elephant tracks ceased, and presently, as we neared a stream, we came to a mangrove swamp. It was almost like seeing an old friend, or, I may say, an old enemy, for the remembrances of mosquitoes, tedious navigation, and malaria which the mangrove tree brought to my mind were by no means pleasant. It is not very pleasant to be laid up with African fever, I assure you.
From a mangrove tree to a mangrove swamp and forest is but a step. They never stand alone. Presently we stood once more on the banks of the little stream, whose clear, pellucid water, had so charmed me a little farther up the country. Now it was only a swamp, a mangrove swamp. Its bed, no longer narrow, was spread over a flat of a mile, and the now muddy water meandered slowly through an immense growth of mangroves, whose roots extended entirely across, and met in the middle, where they rose out of the mire and water like the folds of some vast serpent.