Butterflies doing strange things in very beautiful ways were in my mind when I sat down, but by the time my pen was uncapped my thoughts had shifted to rocks. The ink was refractory and a vigorous flick sent a shower of green drops over the sand on which I was sitting, and as I watched the ink settle into the absorbent quartz--the inversions of our grandmothers' blotters--I thought of what jolly things the lost ink might have been made to say about butterflies and rocks, if it could have flowed out slowly in curves and angles and dots over paper--for the things we might have done are always so much more worthy than those which we actually accomplish. When at last I began to write, a song came to my ears and my mind again looped backward. At least, there came from the very deeps of the water beyond the mangroves a low, metallic murmur; and my Stormouth says that in Icelandic _sangra_ means to murmur. So what is a murmur in Iceland may very well be a song in Guiana. At any rate, my pen would have to do only with words of singing catfish; yet from butterflies to rock, to fish, all was logical looping--mental giant-swings which came as relaxation after hours of observation of unrelated sheer facts. The singing cats, so my pen consented to write, had serenaded me while I crossed the Cuyuni in a canoe. There arose deep, liquid, vibrating sounds, such as those I now heard, deep and penetrating, as if from some submarine gong--a gong which could not be thought of as wet, for it had never been dry. As I stopped paddling the sound became absolute vibration, the canoe itself seemed to tremble, the paddle tingled in my hands. It was wholly detached; it came from whatever direction the ear sought it. Then, without dying out, it was reinforced by another sound, rhythmical, abrupt, twanging, filling the water and air with a slow measure on four notes. The water swirled beside the canoe, and a face appeared--a monstrous, complacent face, such as Böcklin would love--a face inhuman in possessing the quality of supreme contentment. Framed in the brown waters, the head of the great, grinning catfish rose, and slowly sank, leaving outlines discernible in ripples and bubbles with almost Cheshire persistency. One of my Indians, passing in his dugout, smiled at my peering down after the fish, and murmured, "Boom-boom."