The Montgomery advertiser. [volume] (Montgomery, Ala.) 1885-1982, 1904-06-12

some cases. to the vanishing point as
the sun rises higher and higher. the
latter Increasing In density and ex-
tent during the same period. That
these dark markings are not due to
shadows Is shown by the fact that
they are most conspicuous at full moon
when shadows are impossible.
The method to be employed by the
Harvard astronomer in further study
| OF these changes in the moons appear
ance is interesting. He has had a
dozen Of the hundred and more photo
l graphs of his atlas representing as
many periods in the lunar day, repro
duced in half-tone. and takes with
him series OF prints on which he Will
sketch in with a lead pencil each night
from actual observation the extent OF
the Ice fields and of the vegetation
patches. In this way ii will be posi-
bic to verify many of the differences he
has drawn, and likely, to supplement
and expand them
/ The peculiarities of the crater Plato,
(which has a broad, fiat floor dotted
with little craters-or craterlets, as
they are called-are also to be studied
from Echo Mountain. Seventy of these
craterlets have been reported by diff
| feient observers, but they change con-
stantly, appearing and disappearing,
and Professor Pickering wishes to check
/ them up, so to speak. They were first
observed by a committee of British as
trcnomers in 1870 and again in 1881.
In 1892 Professor Pickering made an
| other examination of them, and now
that It, Is possible to construct map
showing all the discoveries in the era
ter Plato. both confirmed and uncon-
armed, a proper time seems to have
arrived for making a final authorita-
/ tive record
| While he is at Echo Mountain, Pro-
fessor Pickering will also make some
further observations of Jupiter's satel-
lites. When he was at Arequipa he
found that all these bodies were. ap
parently. g-shaped. and that one, at
least. revolved end over end, so that
sometimes 1t presents a round disk to
the observer. and at others luminous
broadside With the very favorable at
mospheric conditions in California he
hopes to get a more perfect view of
these interesting little moons. and to
confirm his previous conclusions.
Although very close study has been
| made of the craters of the moon noun
tsns II would naturally be of great
advantage If they could be examined by
ever, science has as yet not progressed
far enough for that, the next best plan
an astronomer in person. Since, how
Is to visit formations on the earth's
surface that are similar to those on
the moon. These are found ir their
best estate in the volcanoes of Hawaii
among which Professor pickle: ing will
spend a month Terrestrial volcanoes,
IL should be said are Of two kinds
those caused by eruptive explosions,
like Vesuvius and Pele, and those caus-
eo by engulfment. or the slow caving
In of the earth's crust. The latter class
resembles the typical lunar mountains
f1xr
Hawaii. The four which Professor
Tit kering will particularly examine are
Kilauea, the volcano which every trav-
eler visits In Hawaii, and which is still
very much alive; Mauna Lao, a noun
tain 10000 feet high and not very ia
miliar to the ordinary traveller; Mauna
Kea, 1000 feet higher but now extinct,
and Haleakala, an extinct monster with
crater four or five miles In diameter
and two thousand feet deep Even
when they are in full vigor volcanoes
of this type are perfectly approachable
and 1t is safe for the scientific man to
climb down into their craters and OBJ
serve their inner workings
On his way home Professor Picker
ing will spend several days among the
geysers of the Yellowstone Park The
geysers issue from craters very SINH
lar to certain craters on the moon from
which streams seem once to have flow
ed; and II Is interesting that the dry
riVerbeds of the moon, IL that is what
they are. show popularity observed
In dried-up water-courses of the West
err deserts: they are widest at their
sources and gradually taper away to a
vanishing point--which is, of course
contrary to the usual development OF
terrestrial rivers
Altogether. the Investigations Profess
sor Pickering is about to. make promise
to bring us more intimate knowledeye
than we now have of our nearest celes-
tial neighbor.