We were still seated at our meal, when a low rumbling noise reached our ears. It continued for some time, and looking out towards the east, whence it appeared to come, we saw dark clouds collecting. Presently vivid flashes of lightning darted forth, and reiterated roars came pealing through the air. "We must get shelter up immediately," cried Senhor Silva, "or the young ladies will be wet through; and our goods may suffer too." The canoes had been well secured to trunks of trees, though not unladen. We immediately got out the axes, and commenced cutting down the smaller saplings and straight branches of trees as rapidly as we could. These we placed on the side of the bank, covering our rude hut over with large leaves and heavy boughs on the top, which we secured by rattans to prevent their being blown away. Everything that could be injured by rain was immediately brought up, leaving room for the young ladies and poor Igubo in the centre. "Oh, we can perch ourselves on the top of the baggage," cried Leo. "There will be room then for all hands inside." While we were working away the clouds came rushing on over the sky, the flashes of lightning becoming every instant more vivid and frequent. I had hitherto seen nothing like it on shore. The most vivid flashes of forked lightning darted from the clouds, apparently playing round the summits of the taller trees, and then descending, went zigzagging along over the ground. Others were seen traversing the river in all directions. It was a grand but terrific scene. The blacks looked alarmed, and poor Chico chattered as if he would shake his teeth out, and clung to Jack's neck for protection. The thunder roared and rattled louder and louder, till we could scarcely hear each other speak; while sometimes the whole atmosphere seemed filled with flame. Presently huge drops began to fall. They came thicker and thicker, till they splashed down upon the river, throwing up miniature waterspouts all over it. The roar of the splashing and pattering was quite deafening. The wind, too, howled through the trees, which threatened to come down upon our heads, though we had placed our hut as far from them as possible. In a few minutes the water, which had been perfectly clear, became thick and muddy, and branches of trees and logs of wood were seen floating down the stream. "We should be thankful that we are safe on land," said David. "Will this last long, Senhor Silva?" "Sometimes such storms are over in half an hour," was the answer; "but they may last for a couple of days. Should this do so, we may congratulate ourselves on having the canoes to escape in, for the river may speedily swell, and cover the very spot where we are sitting."