A thousand one such reflections whirled in succession through his brain; and, resting his head between his hands, he sat there for hours without raising it.
"We must make one final effort," he said, at last, about ten o'clock in the morning. "We must endeavor, just once more, to find an atmospheric current to bear us away from here, and, to that end, must risk our last resources."
Therefore, while his companions slept, the doctor raised the hydrogen in the balloon to an elevated temperature, and the huge globe, filling out by the dilation of the gas, rose straight up in the perpendicular rays of the sun. The doctor searched vainly for a breath of wind, from the height of one hundred feet to that of five miles; his starting-point remained fatally right below him, and absolute calm seemed
