unchanged, I should arrive at the orbit of Mars some days earlier than intended, and at a point behind that occupied by the planet, and yet farther behind the one I aimed at.  Prolonged observation and careful calculation had so fully satisfied me of the necessity of the corrections in question, that I did not hesitate to alter my course accordingly, and to prepare for a descent on the thirty-ninth instead of the forty-first day.  I had, of course, to prepare for the descent very long before I should come within the direct influence of the attraction of Mars.  This would not prevail over the Sun’s attraction till I had come within a little more than 100,000 miles of the surface, and this distance would not allow for material reduction of my speed, even were I at once to direct the whole force of the apergic current against the planet.  I estimated that arriving within some two millions of miles of him, with a speed of 45,000 miles per hour, and then directing the whole force of the current in his direction, I should arrive at his surface at a speed nearly equal to that at which I had ascended from the Earth.  I knew that I could spare force enough to make up for any miscalculation possible, or at least probable.  Of course any serious error might be fatal.  I was exposed to two dangers; perhaps to three:  but to none which I had not fully estimated before even preparing for my voyage.  If I should fail to come near enough to the goal of my journey, and yet should go on into space, or if, on the other hand, I should stop short, the Astronaut might become an independent planet, pursuing an orbit nearly parallel to that of the Earth; in which case I should perish of starvation.  It was conceivable that I might, in attempting to avert this fate, fall upon the Sun, though this seemed exceedingly improbable, requiring a combination of accidents very unlikely to occur.  On the other hand, I might by possibility attain my point, and yet, failing properly to calculate the rate of descent, be dashed to pieces upon the surface of Mars.  Of this, however, I had very little fear, the tremendous power of the apergy having been so fully proved that I believed that nothing but some disabling accident to myself—­such as was hardly to be feared in the absence of gravitation, and with the extreme simplicity of the machinery I employed—­could prevent my being able, when I became aware of the danger, to employ in time a sufficient force to avert it.  The first of these perils, then, was the graver one, perhaps the only grave one, and certainly to my imagination it was much the most terrible.  The idea of perishing of want in the infinite solitude of space, and being whirled round for ever the dead denizen of a planet one hundred feet in diameter, had in it something even more awful than grotesque.