In fact, we had no control of the craft in this distance, and it was fortunate that there was nothing worse to be here encountered.

The whirlpools were the most perfect specimens I ever saw.

Usually they were about twenty feet in diameter, drawing evenly down toward the vortex, the centre being probably about eighteen inches to two feet below the rim.

The vortex at the top was about six to ten inches in diameter, diminishing in five or six feet to a mere point at the bottom.

Our boats were twenty-two feet long, and as they were turned around in these whirls they about reached across them, while we could look over the side and see the vortex sucking down every small object.
The opposite of these was the fountains, or boils, where the surface was exactly the reverse of the whirls: a circular mass of water about twenty feet in diameter would suddenly lift itself a foot or two above the general surface with a boiling, swirling movement.