And while I stood thus rooted to the ground, the sweat standing in large drops on my forehead, all at once close to me sounded a cry, fine and clear at first, and rising at the end to a shriek so loud, piercing, and unearthly in character that the blood seemed to freeze in my veins, and a despairing cry to heaven escaped my lips; then, before that long shriek expired, a mighty chorus of thunderous voices burst forth around me; and in this awful tempest of sound I trembled like a leaf; and the leaves on the trees were agitated as if by a high wind, and the earth itself seemed to shake beneath my feet. Indescribably horrible were my sensations at that moment; I was deafened, and would possibly have been maddened had I not, as by a miracle, chanced to see a large araguato on a branch overhead, roaring with open mouth and inflated throat and chest. It was simply a concert of howling monkeys that had so terrified me! But my extreme fear was not strange in the circumstances; since everything that had led up to the display--the gloom and silence, the period of suspense, and my heated imagination--had raised my mind to the highest degree of excitement and expectancy. I had rightly conjectured, no doubt, that my unseen guide had led me to that spot for a purpose; and the purpose had been to set me in the midst of a congregation of araguatos to enable me for the first time fully to appreciate their unparalleled vocal powers. I had always heard them at a distance; here they were gathered in scores, possibly hundreds--the whole araguato population of the forest, I should think--close to me; and it may give some faint conception of the tremendous power and awful character of the sound thus produced by their combined voices when I say that this animal--miscalled "howler" in English--would outroar the mightiest lion that ever woke the echoes of an African wilderness. This roaring concert, which lasted three or four minutes, having ended, I lingered a few minutes longer on the spot, and not hearing the voice again, went back to the edge of the wood, and then started on my way back to the village. Perhaps I was not capable of thinking quite coherently on what had just happened until I was once more fairly outside of the forest shadows--out in that clear open daylight, where things seem what they are, and imagination, like a juggler detected and laughed at, hastily takes itself out of the way. As I walked homewards I paused midway on the barren ridge to gaze back on the scene I had left, and then the recent adventure began to take a semi-ludicrous aspect in my mind. All that circumstance of preparation, that mysterious prelude to