The Salt Lake herald. [volume] (Salt Lake City [Utah]) 1870-1909, 1896-04-12
IMPOSING LUNAR MOUNTAIN
RANGES.

Returning, however, to the Feighbor
ing coasts from our survey of these OBJ
Jects out in the are Imbrium, we per-
ceive the splendid range of the lunar
Apprentices. The objects so called, are
by far the most magnificent range of
mountains that can be seen on the moon
ascending, as some of its peaks do, to
an altitude of about 1900 feet above the
surrounding plain. This superb range ex-
tends for a distance of no less than 400
miles along the shore of the Mare I'm
brium, and the special SUBMITS which
have been noticed upon it are to be num-
bered in hundreds. The Apprentices pro-
Ject mighty promontoC'y into the Mare
Imbrium, which terminates in the crater
knows as Erathathenes. This object is
of interest as being perhaps the volcanic
vent for the mighty forces which were
once concerned in the upheaval of this
mountain range connected with it,
The promontory thus magnificently end
ed, points to another lunar feature. This
is the great crater Copernicus, which is
regarded, and I believe justly regarded,
as the most noteworthy object on the
moon. 1t stands isolated in the Oceanus
Procellarum, and this peculiar situation
gives to Copernicus distinctness 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 mile in altitude Among
the features which make Copernicus spe-
cially interesting as telescope objects,
are the remarkable terraces which are
to be seen in its interior. They are ap-
parently due to successive floodings of
the crater by lava. 1t seems probable
that they were produced in the following
manner: Suppose that in connection with
some outbreak the crater became filled
with lava, then after period of quies-
cence, the surface of this would be-
come CONCEALED. If the molten lava be-
meath subsidized it would doubtless leave
a margin of solicited material, which
would thus form the first ~ highest ter
race. At a subsequent outbreak the ba-
sin might have been only partially filled,
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
forming a second terrace.
I must here specially mention re-
markable characteristic of lunar seen
cry which is displayed on grand scale
by Copernicus, I alluded to the presence
of bright radiating streaks which extend
from the great crater for many hundreds
of miles over the lunar surface. The ex-
PLANTATION of these bright streaks offers
one of the most difficult problems in
lunar physics They are sometimes
thought to mark lava-fows from the CEN
trail spot at some earlier phase of erup-
ton 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 characterizes them.
Near IDe SOUTHERN pure VI lie ilIOOh IL
the remarkable crater known as Tycho
This is situated in region where the
scenery indicates the widest and most
magnificent confusion Tycho is specially
noticeable for the number of bright
streaks which radiate from it: Indeed, al
the time of full moon, when these streaks
are peculiarly visible, they have fire.
quently been likened to meridians di
verging from the pole. Nasmyth suppos-
ed that these streaks were due to cracks
in the moon and that through these
cracks lava had welled out from be
meath. He gives a striking illustrator
of the mechanical possibility of this doc
trine by showing how a glass globe has
been observed to crack in such way
as to produce a system of streaks exact
1y resembling those seen to diverge from
| Tycho on the moon.
1t is known that great volcanic out
breaks on the earth, such for example
| as the renowned discharge which tool
place at Krakatoa in 1885, have beer
/ attended with the evolution of enormous
! quantities of volcanic dust, or comminut
ed purnice, which was of light grayisf
color 1t may, as Mr.. Elger suggests, per
haps have happened that volumes of vol
canic dust have issued from the assures