Memba Sasa and Simba wiped the sweat from their faces. It seemed that they too had found the work severe. That cheered me up still more. Simba grinned at us, and, worming his way backward with the sinuousity of a snake, he disappeared in the direction from which we had come. F. cursed after him in a whisper both for departing and for taking the risk.
And any circulation of the layers of water at different temperatures, by reason of their unequal specific gravities, seems to be very much interrupted by the narrowness and sinuousity of the passage. The intermitting springs of Iceland are probably caused by the existence of caverns, in which the vapor is retained by the pressure of the column of water in the channel which leads to the surface.