The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1900-06-03

sun gradually sinks and the ferceness OF
its heat becomes a little tempered, Lime
begins 10 increase again in diameter and
when the sun gets near the horizon the
wonderful spot is seen TO have almost re-
gained the magnitude that 1t had just after
emerging from the lunar night.
These changes suggest frost spreading In
the shadow and receding in the sunshine.
or a cloud alternately growing and con-
tracing under similar influences. The fact
discovered by Professor Pickering that
even the shadow OF the earth falling for a
short time upon the spot causes IL 10 ex-
pand 10 a measurable degree shows how
sensitive IL is 10 alterations of temperature
But frost or a cloud upon the moon pre-
supposes an atmosphere and vapors there.
They certainly must be widely different
from such things upon the earth, but IL
they are abundant enough TO cause motions
and changes visible 10 our eyes. their pres
ence may possibly indicate the existence of
yet more interesting things in the lunar
world.
1t should be added-because the fact,
while at present increasing the mystery,
may In the end aid in solving it-that
changes lik those witnessed in Lime do
not appear TO a1ect most Of the other we'll
known markings on the moon. At the time
OF his eclipse observations Professor Pick
ering carefully watched three or four re-
markable localities or the lunar surface.
where craters yawn or fiat plains lie ex-
tended, but not the slightest alteration was
observed in their forms or appearance dur
ing the time that Lime was expanding I'M
1SA LIN III tllt&L VI tAC II - ldlON
and then shrinking again as the untem-
pered blaze of the sun fell upon il.
There is, however, at least one other To-
cality on the moon where curious changes
or similar origin have been detected-the
ring-shaped plain called Plato. This is also
in the northern lunar hemisphere, about 500
miles from Lime. 1t is astonishingly regu-
lar in outline, about sixty miles In dame
ter, very fiat and completely encircled with
lofty, steep and sharp-peaked mountains
as fine a valley for a nation of hermits TO
inhabit as could we'll be imagined. A few
thousand Boer rif1emen stationed on the
kopjeS of Plato could make il safe from in
vasion against the entire lunar world. In
this singular mountain-ringed valley il has
been noticed that the rising sun, just peer
ing above the surrounding peaks. looks
down upon a vast whitish gray expanse,
filling the whole of the immense interior.
But as the solar orb swings clear of the
mountain tops and the shadows of the pin
nacles and ridges become shorter upon the
plain beneath the gray color first brightens
and then rapidly fades over all the surface
of the valley until at lunar noon Plato has
turned almost black, while at the same
time its inclosing mountains of chalky
whiteness are ablaze with the sunshine.
with the remarkable phenomena reported
by Professor Pickering. indicate that there
are certain places on the moon where the
contrast between daylight and darkness or
between heat and cold manifests peculiar
effects, and In those places the search for
further discoveries should be pushed. Some
day our silent satellite may astonish US
with revelations of greater human interest
than any that faraway Mars can offer.