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The Unparalleled Adventures of One Hans Pfaal
by
“The stupor and surprise produced in my mind by this extraordinary change in the posture of affairs was perhaps, after all, that part of the adventure least susceptible of explanation. For the bouleversement in itself was not only natural and inevitable, but had been long actually anticipated as a circumstance to be expected whenever I should arrive at that exact point of my voyage where the attraction of the planet should be superseded by the attraction of the satellite — or, more precisely, where the gravitation of the balloon toward the earth should be less powerful than its gravitation toward the moon. To be sure I arose from a sound slumber, with all my senses in confusion, to the contemplation of a very startling phenomenon, and one which, although expected, was not expected at the moment. The revolution itself must, of course, have taken place in an easy and gradual manner, and it is by no means clear that, had I even been awake at the time of the occurrence, I should have been made aware of it by any internal evidence of an inversion — that is to say, by any inconvenience or disarrangement, either about my person or about my apparatus.
“It is almost needless to say that, upon coming to a due sense of my situation, and emerging from the terror which had absorbed every faculty of my soul, my attention was, in the first place, wholly directed to the contemplation of the general physical appearance of the moon. It lay beneath me like a chart — and although I judged it to be still at no inconsiderable distance, the indentures of its surface were defined to my vision with a most striking and altogether unaccountable distinctness. The entire absence of ocean or sea, and indeed of any lake or river, or body of water whatsoever, struck me, at first glance, as the most extraordinary feature in its geological condition. Yet, strange to say, I beheld vast level regions of a character decidedly alluvial, although by far the greater portion of the hemisphere in sight was covered with innumerable volcanic mountains, conical in shape, and having more the appearance of artificial than of natural protuberance. The highest among them does not exceed three and three-quarter miles in perpendicular elevation; but a map of the volcanic districts of the Campi Phlegraei would afford to your Excellencies a better idea of their general surface than any unworthy description I might think proper to attempt. The greater part of them were in a state of evident eruption, and gave me fearfully to understand their fury and their power, by the repeated thunders of the miscalled meteoric stones, which now rushed upward by the balloon with a frequency more and more appalling.
“April 18th. To-day I found an enormous increase in the moon’s apparent bulk — and the evidently accelerated velocity of my descent began to fill me with alarm. It will be remembered, that, in the earliest stage of my speculations upon the possibility of a passage to the moon, the existence, in its vicinity, of an atmosphere, dense in proportion to the bulk of the planet, had entered largely into my calculations; this too in spite of many theories to the contrary, and, it may be added, in spite of a general disbelief in the existence of any lunar atmosphere at all. But, in addition to what I have already urged in regard to Encke’s comet and the zodiacal light, I had been strengthened in my opinion by certain observations of Mr. Schroeter, of Lilienthal. He observed the moon when two days and a half old, in the evening soon after sunset, before the dark part was visible, and continued to watch it until it became visible. The two cusps appeared tapering in a very sharp faint prolongation, each exhibiting its farthest extremity faintly illuminated by the solar rays, before any part of the dark hemisphere was visible. Soon afterward, the whole dark limb became illuminated. This prolongation of the cusps beyond the semicircle, I thought, must have arisen from the refraction of the sun’s rays by the moon’s atmosphere. I computed, also, the height of the atmosphere (which could refract light enough into its dark hemisphere to produce a twilight more luminous than the light reflected from the earth when the moon is about 32 degrees from the new) to be 1,356 Paris feet; in this view, I supposed the greatest height capable of refracting the solar ray, to be 5,376 feet. My ideas on this topic had also received confirmation by a passage in the eighty-second volume of the Philosophical Transactions, in which it is stated that at an occultation of Jupiter’s satellites, the third disappeared after having been about 1″ or 2” of time indistinct, and the fourth became indiscernible near the limb.{*4}