The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1888-03-04
INSTRUMENTATION
Prof Richard A. Proctor Tells All About
the Moons Past, Present and Future.
What the Noon Is Now-Her Light-The
Moons Past-Her Fiery Yoath-Her Mid
Life-What Signs of Past Fitness for Life.

The moon regarded as an object of physical
study. occupies a unique position among tns
members OF our solar system. Some Oh the
other planets-for the moon be it remembered.
IL a planet a companion world of the earth, no
mere satelIite-tell Of the past OF our eartns
career; others again tell us of the future; out
the moon speaks both of the past and future OF
world life. We can study her surface TO learn
what our earth viii be like when old age and
death overtake her; but we can also STUDY the
moons surface to learn something ABOUT our
esrths condition IN the past
she retains the record OF stages of life through
which she passed millions Of years ago. and
through which our earth has also passed, but
from the earth's face the records Of these past
stages have BEEN in great degree, removed,
blurred and defaced, till we are unable to read
them Alright
Let ms consider the moon in both aspects, be-
ginning with the lessons she teaches us respect
ing the past.
1t is easy to see why the moons surface should
be mach less affected by atmospheric and
aqueous wear and tear, during the past ages
when she had atmosphere and when she had
seas. In the first place the period of time
during which she thus clothed with air and
water must have been much shorter than the
corresponding period for the earth. AS much the
smaller orb. having in fact but the eighty first
part of the earth's mass. she would
necessarily cool far more rapidly-Drobably
Though 1 will not here enter on the calculations
which indicate the probability about six times
faster than the earth; so that if set the past
duration of the esrths fitness for life at 60 OO0-
900 years which biologists would regard as a
moderate estimate for the duration OF the
ArchRan, primary, secondary, tertiary and re-
cent eras we should have TO regard 10000 900
enf fb0d fIPa n
part of the moons life. The work OF denudatlon,
which has gone upon the earth during the
past go 000, 600 of years. could not possibly have
been accomplished upon the moon during IOOOO,-
600 years, even though the work had proceeded,
century by century. at the same rate. But IL
could not proceed nearly so fast on the moon as
on the earth To begin with, there must have
been much less air and water per square mile or
the moons surface than on the earths IN cor
responding portions of the life of each As
Stunning the air and water to be the
same proportions of the total mass of each
planet, the earth had eighty-one times As much
air and water as the moon, and the eartns at
mosphere ana water covered a surface not
eighty-one times, but only thirteen and one-half
times the surface of the moon, so that on our
reasonable assumption as TO the quantity of air
and water present the two planets, the earth
had SIX times as much air and water over each
square mile of her surface as che moon had at
che corresponding stages or her lire as a world.
With a sixth part only of these. the instruments
of denuoation, the moon had also but
sixth part of the energy with which to
times as strong as gravity on the moon;
and gravity each planet was the hand by
which air and water. the tools of denudation.
were worked. With tools having but one-sixth
the efficiency. the force of lunar gravity having
but one-sixth the energy of terrestrial gravity.
and working for but sixth part of the time.
could do such work in destroying the
primeva features of the planet has been ac-
complished our earth. We may then expect
20 find in the crust Of the moon, stripped as it
now is of the air and water which once surround
ed it, the records of the original rock-surface
corresponding to the Archsean rock of our
earth.
Biologists admit that the condition of the
earths surface before the primary strata began
TO be formed cannot be satisfactorily determined
Although certain parts of the still remaining
crust are called Archaean 1t Is very doubt
full whether they really represent the primeval
crust. There is much better chance that in
portions OF the income surface the primeval rock
will still remain in something like its primeval
condition; so that we may be able to read por-
ton of the past history of the earth better in
neiehbor world the moon than in our own, just
can form better idea of the nature of our
savage ancestry by studying the ways and man
ners Of less civilized races of to-day than from
any evidence that we obtain from the study
of the records of our own race.
Thus studying the moon see the traces of
the earlier vulcaniRn stages of her career,
stages such our earth and every planet passes
through. We SEQ first how the still plastic
crust was riven for distances of many hun
dreds of miles by the action of the interior
forces; aud we can see where molten matter
flowed through those riffs and spread in ribbon
like strips over the hidden seams. Later. the
process of contraction began chiefly to affect the
crust, while the nuclear matter retreated from
1t, we how immense corrugations were
formed, akin to those of wrinkled skin or Of
6hriveied apple.
OF these stages of earth-life traces still re-
main. Geoloeists@had indeed already shown
that the earth must have passed through them
But the evidence in the earth's case is reconcile
and obscure. In the moons it is striking and
obvious. Biologists had to study the structure
of strata deep down below those which form the
main portions OF noun tain, masses, before they
came on evidence of that primeval rifting, fol-
lowed by the outflow of molten matter, which
led to the sinking of the crust in the parts thus
broken and overloaded. and to their receiving
larger supplies OF matter deposited on the
trouRh-like portions of the floor thus
formed. OF the original corrugations formed
later as the ancient ernst contracted, we have
evidence In the existence OF mountain ranges;
not ths3 mountain ranges are themselves such
corrugstons, as we once supposed, but it has
been by the contraction of the crust, necesear.
lily leading 20 a crumping and wriuklIne of its
substance, that the material of the mountain
ranges raised above the level. This
material was deposited originally in the trough
like depressions just referred to, to depths
amounting in some cases to ten or twelve miles.
But under the side pressure exerted on the con-
tracing crust these immense seams of matter
were shouldered, so TO speak, above the mean
level, to greater and greater heights until those
preGsures had expended their energies On the
moon we can in many places the corruea-
lions themselves Into which the crust was
crumpled in the process of contraction.
On the moon. again. we find an immense num-
her of craters. ranging in size from mere saucer
shaped depressIons less than half mile wide to
gigantic orators having a span of more than one
hundred miles. In height the crater rings range
from few hundred yards TO to 1000 or s. OO0
Now, or the earth there are many craters, but
none which either resemble the great lunar
craters in form, or can be compared with them
for size. Yet cannot reasonably doubt that
in earlier stages of her vulcanan past the earth
had such craters as still remain on the moon
There are indeed. parts OF the earth where the
traces of such craters still remain. In the Isle
Of Null for instance I'm the Inner Hebrides),
there is the basal wreck of great volcanic ring
which must have been thirty miles wide and
twelve or thirteen thousand feet high. ought
rather perhaps say that the Isle of Null itself
Is the basal wreck of that crater, long since
! uced to a mere ring of hills by the denuding
forces Of sir and water.
And while the moon is thus interesting and
in regard to the past, she has much
TO tell also respecting the future of