The Hickman courier., 1877-08-10
THE DUMB-BELL NEBUEA.

In Vulpecula there is a re marketable
object called the Dumb-bell nebula, or
star-cloud. 1t cannot be seen well
without a very powerful telescope. 1t
was formerly thought 10 consist entirely
of small stars, so remote that they
could not be separately discerned; but
it has lately been discovered that the
greater part of this nebula's light comes
from glowing gas. The vastness of the
space occupied by this cloud of luminous
gas will be nderstood-though no
mind can possibly conceive it when
/ mention that at the distance OF. the
nearest of the fixed stars the whole of
our solar system would appear but as
a mere point, even in a powerful tele-
scope. The Dumb bell nebula covers
quite a large space as seen in such an
srusnent. It is also, probablys much
si Isf q 4; = IS. .'lsgsssstxea stars;
~,sescheTto- occupy a region OF
pace exceeding many times that
through the planets of our solar system
pursue their paths, Yet the span of our
earth's path around the sun is fully one
hundred and eighty-four millions of
miles, while Neptune-the remotest
planet of the solar ystem-travels
thirty times farther from the sun,
having thus an orbit spanning more
than five thousand millions of miles.
A globe Just fitting the path of Nep-
tune would contain many qualrillions
of cubic miles'-and probably the
Dumb bell nebula exceeds such globe
in volume (or, to speak more exactly,
occupies a space exceeding such a globe
in volume) many millions Of times
Very strange Is the thought that as
tronomers should have been able to find
out what this mighty mass of glowing
gas consists Of Placed yonder amid the
glories of the milky way, lost to human
vision through its vast remoteness, only
brought within our view at all by means
of powerful telescopes, and only reveal
ing its true shape when seen with the
most powerful telescopes men have yet
constructed, what at first sight can seem
more amazing than that men should be
able to tell what kind of substance it is
which gives out the misty luster of that
cloudlet in space? The very light which
comes to us from the Dumb-bell nebula
has probably taken hundreds Of years in
crossing the tremendous space separating
us from that object. Yet that light / is
conveyed its message truly. Examined
with that instrument, the spectroscope,
whose Office | lately described in pa
per on the planet Venus,-the light of
the Dumb-bell nebula presents, not the
rainbow-tinted streak which comes from
glowing solid and liquid bodies, but three
bright lights only. At least three lines
are seen If the nebula Is examined
through a fne slit if the field Of view Is
opened, there are seen three faint images
of the cloudlet. The correct way of
sieaeribing what the spectroscOpe tells Us
about this object is to say that, instead of
its light presenting all the colors Of the
Adl4bBh3 IL - ADAAAANAs NAtiA cAAbINA ~ 1AAN
spectroscope, to contain three colors only,
all of them greenish, but slightly different
in tint One Of the colors is precisely
such tint of green as comes with four
other colors) from glowing hydrogen gas,
and shows us that there are enormous
masses OF hydrogen in that remote cloud !;
another tint shows, in like manner, that
there are immense masses of nitrogen !;
but the third tint has not yet been foU9 I'D
to correspond with q tint emitted by aAy
known substance The skein of light
from that double fluff ball has thus been
unraveled by the spectroscope, after
journeying millions of millions of miles,
and has been sorted into three tints, two
of which have been matched against the
known tints of earthly gases, but the
third remains as yet unmatched.--Prof.
Z 4. Proctor, ST. Nicholas for august.