myself.
My sleep was of necessity more or less broken. I wished to have eight
hours of rest, since, though seven of continuous sleep might well have
sufficed me, even if my brain had been less quiet and unexcited during
the rest of the twenty-four, it was impossible for me to enjoy that
term of unbroken slumber. I therefore decided to divide my sleep into
two portions of rather more than four hours each, to be taken as a
rule after noon and after midnight; or rather, since noon and midnight
had no meaning for me, from 12h. to 16h. and from 24h. to 4.h. But of
course sleep and everything else, except the necessary management of
the machine, must give way to the chances of observation; it would be
better to remain awake for forty-eight hours at a stretch than to miss
any important phenomenon the period of whose occurrence could be even
remotely calculated.
At 8h., I employed for the first time the apparatus which I may call
my window telescope, to observe, from a position free from the
difficulties inflicted on terrestrial astronomers by the atmosphere,
all the celestial objects within my survey. As I had anticipated, the
absence of atmospheric disturbance and diffusion of light was of
extreme advantage. In the first place, I ascertained by the barycrite
and the discometer my distance from the Earth, which appeared to be
about 120 terrestrial radii. The light of the halo was of course very
much narrower than when I first observed it, and its scintillations or
coruscations no longer distinctly visible. The Moon presented an
exquisitely fine thread of light, but no new object of interest on the
very small portion of her daylight hemisphere turned towards me. Mars
was somewhat difficult to observe, being too near what may be called
my zenith. But the markings were far more distinct than they appear,
with greater magnifying powers than I employed, upon the Earth. In
truth, I should say that the various disadvantages due to the
atmosphere deprive the astronomer of at least one-half of the
available light-collecting power of his telescope, and consequently of
the defining power of the eye-piece; that with a 200 glass he sees
less than a power of 100 reveals to an eye situated in space; though,
from the nature of the lens through which I looked, I cannot speak
with certainty upon this point. With a magnifying power of 300 the
polar spots of Mars were distinctly visible and perfectly defined.
They were, I thought, less white than they appeared from the Earth,
but their colour was notably different from that of the planet's
general surface, differing almost as widely from the orange hue of
what I supposed to be land as from the greyish blue of the water. The
orange was, I thought, deeper than it appears through a telescope of
similar power on Earth. The seas were distinctly grey rather than
blue, especially when, by covering the greater part of the field, I
contrived for a moment to observe a sea alone, thus eliminating the
effect of contrast. The bands of Jupiter in their turn were more
notably distinct; their variety of colour as well as the contrast of
light and shade much more definite, and their irregularities more
unmistakable. A satellite was approaching the disc, and this afforded
me an opportunity of realising with especial clearness the difference
between observation through seventy or a hundred miles of terrestrial
atmosphere outside the object glass and observation in space. The two
discs were perfectly rounded and separately discernible until they
touched. Moreover, I was able to distinguish upon one of the darker
bands the disc of the satellite itself, while upon a lighter band its
round black shadow was at the same time perfectly defined. This
wonderfully clear presentation of one of the most interesting of
astronomical phenomena so absorbed my attention that I watched the
satellite and shadow during their whole course, though the former,
passing after a time on to a light band, became comparatively
indistinct. The
My sleep was of necessity more or less broken. I wished to have eight
hours of rest, since, though seven of continuous sleep might well have
sufficed me, even if my brain had been less quiet and unexcited during
the rest of the twenty-four, it was impossible for me to enjoy that
term of unbroken slumber. I therefore decided to divide my sleep into
two portions of rather more than four hours each, to be taken as a
rule after noon and after midnight; or rather, since noon and midnight
had no meaning for me, from 12h. to 16h. and from 24h. to 4.h. But of
course sleep and everything else, except the necessary management of
the machine, must give way to the chances of observation; it would be
better to remain awake for forty-eight hours at a stretch than to miss
any important phenomenon the period of whose occurrence could be even
remotely calculated.
At 8h., I employed for the first time the apparatus which I may call
my window telescope, to observe, from a position free from the
difficulties inflicted on terrestrial astronomers by the atmosphere,
all the celestial objects within my survey. As I had anticipated, the
absence of atmospheric disturbance and diffusion of light was of
extreme advantage. In the first place, I ascertained by the barycrite
and the discometer my distance from the Earth, which appeared to be
about 120 terrestrial radii. The light of the halo was of course very
much narrower than when I first observed it, and its scintillations or
coruscations no longer distinctly visible. The Moon presented an
exquisitely fine thread of light, but no new object of interest on the
very small portion of her daylight hemisphere turned towards me. Mars
was somewhat difficult to observe, being too near what may be called
my zenith. But the markings were far more distinct than they appear,
with greater magnifying powers than I employed, upon the Earth. In
truth, I should say that the various disadvantages due to the
atmosphere deprive the astronomer of at least one-half of the
available light-collecting power of his telescope, and consequently of
the defining power of the eye-piece; that with a 200 glass he sees
less than a power of 100 reveals to an eye situated in space; though,
from the nature of the lens through which I looked, I cannot speak
with certainty upon this point. With a magnifying power of 300 the
polar spots of Mars were distinctly visible and perfectly defined.
They were, I thought, less white than they appeared from the Earth,
but their colour was notably different from that of the planet's
general surface, differing almost as widely from the orange hue of
what I supposed to be land as from the greyish blue of the water. The
orange was, I thought, deeper than it appears through a telescope of
similar power on Earth. The seas were distinctly grey rather than
blue, especially when, by covering the greater part of the field, I
contrived for a moment to observe a sea alone, thus eliminating the
effect of contrast. The bands of Jupiter in their turn were more
notably distinct; their variety of colour as well as the contrast of
light and shade much more definite, and their irregularities more
unmistakable. A satellite was approaching the disc, and this afforded
me an opportunity of realising with especial clearness the difference
between observation through seventy or a hundred miles of terrestrial
atmosphere outside the object glass and observation in space. The two
discs were perfectly rounded and separately discernible until they
touched. Moreover, I was able to distinguish upon one of the darker
bands the disc of the satellite itself, while upon a lighter band its
round black shadow was at the same time perfectly defined. This
wonderfully clear presentation of one of the most interesting of
astronomical phenomena so absorbed my attention that I watched the
satellite and shadow during their whole course, though the former,
passing after a time on to a light band, became comparatively
indistinct. The
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