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variation in question。 But again。 The real diameter of the same
comet's nebulosity is observed to contract rapidly as it approaches
the sun； and dilate with equal rapidity in its departure towards its
aphelion。 Was I not justifiable in supposing with M。 Valz； that this
apparent condensation of volume has its origin in the compression of
the same ethereal medium I have spoken of before； and which is only
denser in proportion to its solar vicinity？ The lenticular…shaped
phenomenon； also called the zodiacal light； was a matter worthy of
attention。 This radiance； so apparent in the tropics； and which
cannot be mistaken for any meteoric lustre； extends from the horizon
obliquely upward； and follows generally the direction of the sun's
equator。 It appeared to me evidently in the nature of a rare
atmosphere extending from the sun outward； beyond the orbit of Venus
at least； and I believed indefinitely farther。｛*2｝ Indeed； this
medium I could not suppose confined to the path of the comet's
ellipse； or to the immediate neighborhood of the sun。 It was easy； on
the contrary； to imagine it pervading the entire regions of our
planetary system； condensed into what we call atmosphere at the
planets themselves； and perhaps at some of them modified by
considerations； so to speak； purely geological。
Having adopted this view of the subject； I had little further
hesitation。 Granting that on my passage I should meet with atmosphere
essentially the same as at the surface of the earth； I conceived
that； by means of the very ingenious apparatus of M。 Grimm； I should
readily be enabled to condense it in sufficient quantity for the
purposes of respiration。 This would remove the chief obstacle in a
journey to the moon。 I had indeed spent some money and great labor in
adapting the apparatus to the object intended； and confidently looked
forward to its successful application； if I could manage to complete
the voyage within any reasonable period。 This brings me back to the
rate at which it might be possible to travel。
〃It is true that balloons； in the first stage of their ascensions
from the earth； are known to rise with a velocity comparatively
moderate。 Now； the power of elevation lies altogether in the superior
lightness of the gas in the balloon compared with the atmospheric
air； and； at first sight； it does not appear probable that； as the
balloon acquires altitude； and consequently arrives successively in
atmospheric strata of densities rapidly diminishing I say； it does
not appear at all reasonable that； in this its progress upwards； the
original velocity should be accelerated。 On the other hand； I was not
aware that； in any recorded ascension； a diminution was apparent in
the absolute rate of ascent； although such should have been the case；
if on account of nothing else； on account of the escape of gas
through balloons ill…constructed； and varnished with no better
material than the ordinary varnish。 It seemed； therefore； that the
effect of such escape was only sufficient to counterbalance the
effect of some accelerating power。 I now considered that； provided in
my passage I found the medium I had imagined； and provided that it
should prove to be actually and 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 rarefaction partially similar （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 specifically lighter than any
compound whatever of mere nitrogen and oxygen。 In the meantime； the
force of gravitation would be constantly diminishing； in proportion
to the squares of the distances； and thus； 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。 In accordance with these ideas； I did not think
it worth while to encumber myself with more provisions than would be
sufficient for a period of forty days。
〃There was still； however； another difficulty； 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。｛*3｝ This was a reflection of a nature
somewhat startling。 Was it not probable that these symptoms would
increase indefinitely； or at least until terminated by death itself？
I finally thought not。 Their origin was to be looked for in the
progressive removal of the customary atmospheric pressure upon the
surface of the body； and consequent distention of the superficial
blood…vessels not in any positive disorganization of the animal
system； as in the case of difficulty in breathing； where the
atmospheric density is chemically insufficient for the due renovation
of blood in a ventricle of the heart。 Unless for default of this
renovation； I could see no reason； therefore； why life could not be
sustained even in a vacuum； for the expansion and compression of
chest； commonly called breathing； is action purely muscular； and the
cause； not the effect； of respiration。 In a word； I conceived that；
as the body should become habituated to the want of atmospheric
pressure； the sensations of pain would gradually diminish and to
endure them while they continued； I relied with confidence upon the
iron hardihood of my constitution。
〃Thus； may it please your Excellencies； I have detailed some； though
by no means all； the considerations which led me to form the project
of a lunar voyage。 I shall now proceed to lay before you the result
of an attempt so apparently audacious in conception； and； at all
events； so utterly unparalleled in the annals of mankind。
〃Having attained the altitude before mentioned； that is to say three
miles and three…quarters； I threw out from the car a quantity of
feathers； and found that I still ascended with sufficient rapidity；
there was； therefore； no necessity for discharging any ballast。 I was
glad of this； for I wished to retain with me as much weight as I
could carry； for reasons which will be explained in the sequel。 I as
yet suffered no bodily inconvenience； breathing with great freedom；
and feeling no pain whatever in the head。 The cat was lying very
demurely upon my coat； which I had taken off； and eyeing the pigeons
with an air of nonchalance。 These latter being tied by the leg； to
prevent their escape； were busily employed in picking up some grains
of rice scattered for them in the bottom of the car。
〃At twenty minutes past six o'clock； the barometer showed an
elevation of 26；400 feet； or five miles to a fraction。 The prospect
seemed unbounded。 Indeed； it is very easily calculated by means of
spherical geometry； what a great extent of the earth's area I beheld。
The convex surface of any segment of a sphere is； to the entire
surface of the sphere itself； as the versed sine of the segment to
the diameter of the sphere。 Now； in my case； the versed sine that
is to say； the thickness of the segment beneath me was about equal
to my elevation； or the elevation of the point of sight above the
surface。 〃As five miles； then； to eight thousand；〃 would express the
proportion of the earth's area seen by me。 In other words； I beheld
as much as a sixteen…hundredth part of the whole surface of the
globe。 The sea appeared unruffled as a mirror； although； by means of
the spy…glass； I could perceive it to be in a state of violent
agitation。 The ship was no longer visible； having drifted away；
apparently to the eastward。 I now began to experience； at intervals；
severe pain in the head； especially about the ears still； however；
breathing with tolerable freedom。 The cat and pigeons seemed to
suffer no inconvenience whatsoever。
〃At twenty minutes before seven； the balloon entered a long series of
dense cloud； which put me to great trouble； by damaging my condensing
apparatus and wetting me to the skin。 This was； to be sure； a
singular recontre； for I had not believed it possible that a cloud of
this nature could be sustained at so great an elevation。 I thought it
best； however； to throw out two five…pound pieces of ballast；
reserving still a weight of one hundred and sixty…five pounds。 Upon
so doing； I soon rose above the difficulty； and perceived
immediately； that I had obtained a great increase in my rate of
ascent。 In a few seconds after my leaving the cloud； a flash of vivid
lightning shot from one end of it to the other； and caused it to
kindle up； throughout its vast extent； like a mass of ignited and
glowing charcoal。 This； it must be remembered； was in the broad light
of day。 No fancy may picture the