We moved slowly on, as people naturally would who were about to be overwhelmed in a calamity that threatened their annihilation, while an indefinable sensation of sleepiness and inertia seized the whole of the party. Vultures and other birds of prey screamed dismally, as they hovered round our heads in the greatest excitement, arising either from terror or the anticipation of a rich repast, we could not tell which. These voracious creatures, with great audacity, often descended to within a few feet of the heads of our horses, which seemed terror-stricken at their near approach. I took aim at one of the largest of them with my rifle, and it fell a little to my left, with an impetus I can only compare to the fall of a human being. Directly it touched the ground, it vomited carrion and died. It was many feet in breadth from tip to tip of wing, but we were too perturbed to stop and measure it. When I discharged the rifle, the report was unusually faint, owing to the state of the air; so much so, that my companions, who were not fifty yards behind, scarcely heard it. The wild animals in the jungle which skirted the road, and which, in general, skulk in silence and secresy in their haunts, rent the air with their howlings. The very order of nature seemed about to be reversed, while the long streamers of grey moss swayed backwards and forwards mournfully from the trees, adding to the solemnity of the scene. As the party slowly wended its way through the wilderness, each individual looked round with suspicion, exchanging furtive glances, or now and then uttering some exclamation of alarm--their manner and bearing indicating minds ill at ease. This dismal state of things lasted nearly an hour, after which time nature seemed to recover herself by a sudden throe, for a brisk breeze, which was highly refreshing to our senses, and which was attended by the loud hollow subterranean sound I have before referred to, unexpectedly sprang up, and swept off, as if by magic, the inertia of nature. What made the phenomenon more extraordinary, was the total absence of thunder or lightning. My companions shouted for joy when the hollow moan of the embryo tempest was heard to move off to the eastward (for, as they informed me, it told of deliverance from peril); I felt a sensation of delight I cannot describe, and heartily responded to the noisy demonstration of satisfaction raised by my companions. Our horses, apparently participating in our delight, pricked up their ears, and snorted, fairly prancing with pleasure, tired and jaded as they were after thirty miles' travel through sand, into which they sank at every step fetlock deep, often groaning pitifully.