“The moon’s actual distance from the earth was the first thing to be attended to. Now, the mean or average interval between the centres of the two planets is 59.9643 of the earth’s equatorial radii, or only about 237,000 miles. I say the mean or average interval, but it must be borne in mind that the form of the moon’s orbit being an ellipse of eccentricity amounting to no less than 0.05484 of the major semi-axis of the ellipse itself, and the earth’s centre being situated in its focus, if I could, in any manner, contrive to meet the moon, as it were, in its perigee, the above mentioned distance would be materially diminished. But, to say nothing at present of this possibility, it was very certain that, at all events, from the 237,000 miles I would have to deduct the radius of the earth, say 4,000, and the radius of the moon, say 1,080, in all 5,080, leaving an actual interval to be traversed, under average circumstances, of 231,920 miles. Now this, I reflected, was no very extraordinary distance. Travelling on land has been repeatedly accomplished at the rate of thirty miles per hour, and indeed a much greater speed may be anticipated. But even at this velocity, it would take me no more than 322 days to reach the surface of the moon. There were, however, many particulars inducing me to believe that my average rate of travelling might possibly very much exceed that of thirty miles per hour, and, as these considerations did not fail to make a deep impression upon my mind, I will mention them more fully hereafter.