Page:The works of the late Edgar Allan Poe volumes 1-2.djvu/46

 seemed, therefore, that the effect of such escape was only sufficient to counterbalance the effect of the acceleration attained in the diminishing of the balloon's distance from the gravitating centre. I now considered that, provided in my passage I found the medium I had imagined, and provided it should prove to be essentially what we denominate atmospheric air, it could make comparatively little difference at what extreme state of rarefaction I should discover it—that is to say, in regard to my power of ascending—for the gas in the balloon would not only be itself subject to similar rarefaction, (in proportion to the occurrence of which, I could suffer an escape of so much as would be requisite to prevent explosion,) but, being what it was, would, at all events, continue specitically lighter than any compound whatever of mere nitrogen and oxygen. Thus there was a chance—in fact, there was a strong probability—that, at no epoch of my ascent, I should reach a point where the united weights of my immense balloon, the inconceivably rare gas within it, the ear, and its contents, should equal the weight of the mass of the surrounding atmosphere displaced; and this will be readily understood as the sole condition upon which my upward flight would be arrested. But, if this point were even attained, I could dispense with ballast and other weight to the amount of nearly 300 pounds. In the meantime, the force of gravitation would be constantly diminishing, in proportion to the squares of the distances, and so, with a velocity prodigiously accelerating, I should at length arrive in those distant regions where the force of the earth's attraction would be superseded by that of the moon.

There was another difficulty however, which occasioned me some little disquietude. It has been observed, that, in balloon ascensions to any considerable height, besides the pain attending respiration, great uneasiness is experienced about the head and body, often accompanied with bleeding at the nose, and other symptoms of an alarming kind, and growing more and more inconvenient in proportion to the altitude attained. This was a