Whereupon two ships were specially constructed for the purpose of carrying out this exploration. They were of extraordinary strength, fitted with immensely powerful gas-engines, and provided with a seemingly inexhaustible supply of the necessary chemical agents. A crew of one hundred volunteers embarked in each, and they started together on their perilous expedition. After eighty-five days one of these ships returned, but only twenty-five of her crew were with her; the rest had vanished either by mortal lesion or metronomic misery. The survivors reported the existence of an absolute pandemonium. The crew had succeeded in forcing the ship about fifty miles further into the zone of tempests than any of the former explorers. But further progress was hopeless. The man who before described to me one of the waves as a wandering cataract was among those who escaped, and his escape was a very narrow one indeed. He told me himself that when he got back into port his negative metronomic balance wanted but a few units of the point which would have terminated his career. And though they succeeded in forcing their way out of the tornado, this was only accomplished by putting on such power as threatened to tear the sides out of the ship. One of the Niagara-like waves fell on the sister-ship, and she was never seen again. After this tragedy an act was passed forbidding all attempts to enter the South Sea. Though many volunteers were ready to risk their lives, the legislature refused to sanction such peril. So now the Hesperian knowledge of the Universe, at the period I speak of, may be shortly summed up as follows:—They knew that their place of abode was a spherical cap. Some had at first maintained that it was a circular plain; but this theory was soon exploded. The uniformly circular horizon visible at sea, and on every large plain, and the results obtained from a general survey of the continent by triangulation, combined to discredit the planar and establish the spherical theory. They knew, also, from pendulum and other experiments, that, at a spot coincident with the centre of the presumed sphere on which they lived, an unknown centre of force existed to which all bodies on the surface tended. And beyond this knowledge there was a great blank. What lay outside the cloud-screen or beyond the equatorial ocean had not entered into the Hesperian mind to conceive.