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feet high, goes onward nearly horizontally in several directions to an unexplored extent. During the water, saltpetre was extensively made from the manure of bats obtained from this. The refuse from the manufacture still lies in large heaps at the place of manufacture, near the entrance of the cave. Wishing to explore and measure the cave, I was joined by several amen and boys of that neighborhood. Down we went, each with a candle or torch to light the way, and I also a long tape line and assistant to measure the distance. On we went, taking the main entrance, from which most of the material for making saltpetre had been obtained, it being the largest. At the distance of about three hundred feet, we entered a, large avenue to the right. We found the odor from the bats very unpleasant. Straggling bats flew around us, inquiring why we were there, and large clusters of bats were on the sides of the walls and overhead. Presently, when the ceiling above came within six to eight feet of the ground, the bats became alarmed, and flew in such crowds around as to put out the lights of most of our party, causing us all to retreat hastily and abandon the idea of further explorations. The next day I went with a gentlemen of that neighborhood to see the bats issue from the cave to begin their night's work. When the sun was about half an hour high. we arrived at the entrance of the cave. About ten minutes before sunset a few bats came forth to reconnoitre and see the time of day, and, after doing this, back they went to report; five minutes later, a few came forth, rising twenty-five to thirty feet above the ground, and off they went with an undulatory motion in a more horizontal direction. Thicker and faster they came by thousands, circling round and round until. high above the ground; then away they gaily went over hill and valley. At sunset the ascending column was so thick that the flying bats nearly touched each other. They came forth by millions. Never before had I seen such an exhibition of life-gay, active life. Forth they went, catching insects here and there by thousands and by millions; hence these bats are useful in destroying night-going insects, who hide by day from the birds. I was told that the people living for many miles around that cave were not troubled with mosquitoes, nor with many other night-flying insects.

I have been told of another bat cave, not many miles from Georgetown, in Williamson county. Others are also