The Portland daily press. [volume] (Portland, Me.) 1862-1921, 1896-07-11

the CHARACTERISTICS of the several objects
around the Mare Imbrlum. beginning
at the northern point. we first come TO
the very remarkable bay 9nown as tho
Sinus Iridium. Then comes Plato, and
| then the gulf sweeps round by Ia noble
range of mountains called the Caucasus,
between which and the range of the APP
pennies there is o passage which leads
into the Marc Serontatis.
AT this point the observer will not fail
to notice three splendid rings lying out
| in the Mare Imbrium. The smallest OF
these is the Ambiguous. Directly below
that is the larger ring known as Aristil-
lus, which is thirty-fou miles in diane
ter. Its rampant rises upward of two
miles above the surrounding plain, while
the interior of it is depressed some 3, 600
feet below the level Of the general surface,
ArIstlllus may be regarded as typical
lunar crater, inasmuoh as it is adorned
by lofty mountain peak ascending from
the centre. A view of The multitudes of
details in this mighty extinct volcano
will reward the diiigent student who
has the use of good telescope. II he
should be an artist. he will find ample
scope for practice with his pencil in de-
lineating the many features of this su-
perb pieos of lunar scenery. The third of
the three Orators which form this note
worthy group lies far out in the Mare
lsImbrium, and is the famous lunar object
known as Arohimedes. This crater is
not quite SO large as Plato, but It's floor
presents multitudes of points of interest
to assiduous lunar observers.
Returning, however, to the neighboring
coasts from our survey of these objects
out in the Mare Imbrium, we perceive
the splendid range of the lunar Ap-
| PENNIES. The objects so called are by far
the most magnificent range ofsmountains
that can be seen on the moon, ascending,
as some of the peaks do, to an altitude Of
about Is, 600 feet above the surrounding
plain. This superb range extends for a
distance of no less than 400 miles along
the shore of the Mare Imbrium, and the
special SUBMITS which have been noticed
upon it are to be numb ered in hundreds.
toy IL to the Maze I nj rum, W b oh termi-
mates in the crater known as Eratos-
themes. This object is Of interest as be-
ing, perhaps. the volcanic vent for the
mighty forces which were once concerned
in the upheayal of this mountain range
connected with it.
The promontory thus magnif cently end
ed points to another lunar feature. This
is the great crater Coperncus, which Ia
regard d, and believe justly regarded,
as the most noteworthy object on the
moon. 1t stands isolated in the Ooeanus
Procellarum, and this peculiar situation
gives to Copernious a distiuctness which
makes it very easy to recognize. The
central regions of the ring are adorned
by mountain, some OF whose peaks at
tain about half a mile in altitude
Among the features which make
Copsrnious specially interesting as a
telescope object are the remark able ter
races which are to be seen in It's interior.
They are apparently due to successive
Holdings OF the crater by lava. 1t seems
probable that they were produced in the
following manner: Suppose that in con-
neotion with some outbreak the crater
became filled with lava, then after a
period of quiescence the surface of this
would become CONCEALED. If the molten
lava beneath gu bsided it would leave a
margin of solidified material, whi CHI
would form the first or highest terrace.
At subsequent outbreak the basin
might have been only partially filed, so
that the lava did not ascend to so great
an altitude. This would in due course
become CONCEALED on the surface, and
again the lava would subside, thus form
ing second terrace.
I must here specially mention a re-
markable characteristic of lunar scenery
which is displayed on grand scale by
Copernicus. l alluds to the presence of
bright radiating streaks which extend
from the grcnt crater for many hundreds
of miles over the lunar surface. Z he ex
PLANTATION of these bright strsaks offers
one of the most difficult problems in
lunar physics. They are sometimes
thought to mark lava flows from the. CEN
trail spot at some earlier phase Of erup
tion than the crater as it now stands
would indicate. 1t does not. however,
seem apparent why these streaks should
in this case possess the peculiar bright
ness which chsracterizes them.
Near the southern pole of the moon is
the remarkable crater known as Tyoh o.
This is sit uated in region where the
scenery indicates the widest and most
magnificent confusion. Tyoho is
specially noticeable for the number Of
Fright streaks which radate from it.
Indeed, at the time of the full moon, when
these streaks are peculiarly visible, they
have frequently besn likensd to meridi-
ans liverging from pole. Nasmyth sup
posed that these streaks were due to
cracks in the moon, and that through
these cracks lava had welled out from
beneath. He gives striking illustration
of the mechanical possibility of this doc.
trine, by showing how q glass globe has
been observed to crack in such way as
ito produce system of streaks resembling