Knoxville journal. [volume] (Knoxville, Iowa) 1874-1986, 1876-04-06
The Moon.

| PRoF. SOULE recently lectured on this
subject before the San Francisco School
of Mechanical Arts. He said that, in
using the immense telescopes of modern
| times, one is surprised at the exceedingly
small area that can be examined at one
time, and by the great diminution of light
which appears to take place. A careful
survey Of the surface fills one with aston
| ishment that the placid, silvery moon
should be changed in a ragged, gray,
wrinkled and pockmarked heavenly body.
On turning 10 the brighter portions, we
| find everywhere mountains, volcanoes,
creyasses and precipices OF vast hight or
depth 1t seems to be picture OF desola-
| ton, enthroned upon pedestal OF ashes.
Those mountainous parts reflect brilliant
| light on account Of their volcanic nature,
! the rocks being often smooth and polished,
and their jagged surfaces giving them
power to catch and throw light in every
! direction. The southwestern portion Is
especially volcanic in its appearance. On
close examination, however, we ind long
ranges Of mountains exhibiting no signs
of volcanic action, but in many respects
similar to the Sierras, much sleeper on
one side than the other, and apparently
| formed by similar forces, though as a rule
the volcanic element prevails. Many OF
these mountains are Of immense size; thus
Clayius is 100 miles in diameter, and has
an area of IL, 600 square miles, and turrets
on its walls shootingto an altitude Of 16, 600
feet We next notice the frequent occur
renee of ringed mountains, not more than
ten to fifteen miles in diameter, and almost
perfectly circular in form. They are
found alone upon the level country, or in
groups, and even upon the ridges OF the
walled plain. There are also craters and
pits, which differ chiefly from the others
in their smaller dimensions. There is
also another prominent feature which has
puzzled astronomers, even in the present
day From many of the ringed mountains,
notably from Tycho, Copernicus and
Kepler, are radiations, extending IN some
cases hundreds of miles, which at the full
of the moon glisten with remarkable
brightness They shine a. brilliantly un-
der the oblique as under the vertical rays
of the sun--a fact yet unexplained; they
pass over the tops and through the craters
of volcanoes, and through the valleys in
an uninterrupted course. Or the many
theories concerning them, perhaps the
most reasonable is that they are veins OF
matter elected from below during some
great volcanic or earthquake disturbances,
and in many respects they resemble our
own trap dykes and scines.
Since the time of Calico, astronomers
have painfully, patiently and persevering-
ly mapped every detail of the moons sur
face, until we have lunar Typographical
charts more accurately constructed than
any hitherto constructed of the earth's sur.
face. Photography has recently aided
largely In this work.
BY careful experiments it has been
proven that the light of the full moon is
only LOCO, 900 part of that of the sun, and
that she gives only one-sixth as much light
as would a pure white disk therefore
she is nearer black than white. An
equal sized globe of friedrich or clay
| thrown into the orbit of the moon would
furnish US with light as bright as our own
luminary.
As early as 100, efforts were made to
ascertain If any heat came from the moon,
her rays being concentrated by means of
| lens upon the bulb of thermometer,
with no effect, howeyer and other and
later trials with improved apparatus gave
the same result, or In some cases indicated
t.iat the moon was shedding negative
heat or cold. II was only after the in
| vention of the thermopile that evidences
| of lunar heat were discovered The
| amount was excessively small, however.
Lord Rose, with the aid of his tlree-foot
| rejecting telescope and Thomson's gal
vanometer. shows that little, II any, of this
heat comes from the interior of the moon,
or, in other words, that the body of the
luminary would be cold but from the heat
| absorbed from the sun. This borrowed
heat has been shown to raise the exterior
temperature of our satellite to at least
fifty degrees Fab. As the suns heat and
| light cease TO fall upon her surface and
are lost for fifteen days at u time; and the
remaining heat being radiated into space,
the alterations of temperature must be
something startling and the changes in
the physical features of the body pro-
duced by the enormous expansions and
contractions Of her outer substance must
be great and very destructive.--Scten
american.