ALEXANDER VON HTTMBOLDT. 171
changes of the stars. What seems to us immuta-
bility in the sky, is only apparent, caused by the
incalculable distance and changes operating gradu-
ally to our limited senses, during millenniums; on
every spot of the vault of heaven the same motion
exists as on earth, for in this motion the whole
universe has its existence.
Humboldt had most efficient and celebrated co-
labourers on the field of astronomy, and during his
life an Immense progress In this science has taken
place, as well as the improvement and perfection of
the necessary Instruments. Humboldt was able to
follow this development of astronomical science of the
last sixty years; his position secured him the intimacy
of all great astronomers; he could see from the
observatories, what thousands possessing high attain-
ments only know from description ; he has personally
watched all discoveries made respecting the heavens
and the earth, for more than half a century. Hence
proceeds his knowledge of the universe, his partiality
for the recurrence of the self-discovered laws of this
earth in space, his ingenious explanation of hitherto
unintelligible facts.
The sky exercises a mysterious charm of attraction
over every one—wherever one may look with the
strongest, space-annihilating telescopes, one finds stars-
or luminous nebulas, of which many have already
been resolved into stars; but- there are also starless
regions of which Herschel once said that devastations
Lad there already taken place by time. Humboldt
calls them chasms in the sky, and thinks they are
views Into an infinite depth of space at whose back-
ground another starry expanse lies, whose light cannot
reach us. This view is almost incomprehensible^to
the senses, when it Is known that light travels with.
the speed of 41,518 geographical miles in a second,
and that nevertheless the light of well-known and
therefore relatively very near stars travels twelve
years to reach us, and that Herschel, through his
famed telescope., discovered luminous nebulae whose