New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1879-11-18

PLANEJS-TilE sTEREOPTiCOS ILLUSTRATIONS.
The third lecture the present series of four by
Professor Proctor delivered last night to a
large audience in Chickering Hail. and was
illustrated by interesting stereopticon views The
subject discussed was The Vastness of Time" BY
calculations explained so as to be easily followed
by his hearers, Mr. Proctor showed the age of the
earth, since il n of gas to be five hundred
million years. 1t would take Jupiter three
million years longer than it did the
earth to reach the latter's present condition The
earth will not be as cold as the moon is now for
2.5Oo,0O0,00O years
THE ADDRESS AND THE ILLUSTRATIONS.
large and interested audience gathered in
Chickering Hall last evening TO hear the third Of
the present OF four lectures by the distinguished
English astronomer Richard \. Proctor. The subject
last night "The Vasncss OF Time" Long before
the hour az which the began all the Ia the
haIi were taken and standing only" was sold to
late comcIs.
hnd said the lecturer. substantially. in his
address before the views were displayed,
thai the statement made in my last lecture
that Ihe moon IS more under the influence OF the
SUMS attraction than of the earth's is not
clear to all minds. As the SUMS ~ much
more than that OF the earth being $4,000 times
great and as the attraction increases inversely with
the square OF the distance. being 3s7
mnch, We see how much more the attracts by
pairing the square of 3s7 with $4,000. The moons
path around the sun i slightly waved line. In an
orbit reduced To the diameter OF one yard the variation
would not be- noticed.
Now % come 10 the subject Of tO-nighi's lecture On
tine last occasion spoke you OF the immensely OF
space, taking the steps ont from the earth TO the other
plancis, thence to the sn. and naiyfo the solar ys
tein OF winch IL is part. At as found ourselves
lost In tie ninltude of space. Tonight will take
parallel course with tme First We Will consider
I Cf
and future than that Of the planets, and the solar
TEN thence may consider the higher orders OF time,
until we los. the intnes OF duration. The task
Is not as simple the estimation OF space b the earth
ana the stem to which 1t belongs. No knows the
o tue cartn on this rsiut nearly all the earnest
students OF science are at issuc But some facts
clear. Sc may study the OF the earih and
the processes which nave on and are SIN contnu-
ng. We deposits formed the bottom OF the
then find them ON The surface hardened formations.
subjected 10 the washing OF rain and the rituation OF
We thus may estimate the quantity
Of matter BIZ he amount OF denudaiion and thus come
| at a close determination 81 the earti's age.
1t be- stated on the authority oi Charles Lyell aud
acting upon The eartn 10y lts light aud heat by which all
meteorological changes are produced. There may be
found serious difficulty with TIN, o. where the suns
SHOWS mai me EARN has hen IN it, present "a yifb
vegetation ourisbng. aud the WIND blowing, for very
long period though maE has not necn here 80 long.
How Long II TOOK TIE EARTH TO COOL.
Then II pass back into the preceding ages must
compute the time for the earth to COO! down from
molten state. BischoG. the German, determines by
poriments with molten rock, and he supported by
fIcmholtz. that the period required Tor the earth TO
cool from 1000 degrees Cengrade To 200 degrees Is
$50 900 900 years. BschoG probably erred in underes
umatiDg rather than Ia ovcrestmating the period;
but II we take period probable and add
TO it the succeeding time, have 4JO,OOO.0CO
years since the earth was nenuar mass,
and IN round numbers may declare 5OOOOc,OOO years
the of our planet.
Mucn longer periods required for the larger plan
cts. In estimating time IN planetary o we must apply
Inc stages it, existence. We find tnatf neat Two
mon balls. an ucb H. diameter ana the other two
Incl,s diameter, II WI take twice ~ long for the
e cI 90 D9c mass , II has EIGHT lines s mnch snrf1ee
from when all heat dep part Inc planet Jupiter in
mass l. nearly 3i3 times large the earth; 3i3 is
fi S reach he same density as the earth il
womd iSss COO ea 1fs 70 @ and e%SS
tnc proportion Tor subsequent changes. for Jupiter
$500 600 Ouo, 3.OOOOOO.OOO more years than the
earth. But Jupiter son ur Younger IN DEVELOPMENT
FAR higher iisic-. Following the rule rs the
81 she sun ia 10000 times greater than that OF the
earth. is will be seventy times as great, and We
mud that 1t would take 35,OOOo 100000 years for the
san 10 reach the earth, present state
Considering The smaller orbs, the moon. We find
that thc period Is comparatively brief, Dnt that the
caItn viii reach tie same condition far in the remote
future The moon in mass is 81 times less than the
earth, and Its surface Is as 10 49, by divid-
con coz paratiye age OF the moon is less than the
the earhs rhis gives s30OOOO0 years "a the time 1t
took for tAe 10 reach condition similar 10 the
present Of the eartn's existence The earth is be-
hind The about APO 900 years and the moon
goes ON slx times as a "a we eart iui,
tped by gives IL 100000 years before we shall
see the earth as the moon now Is
THE FUTURE OF THE KARTn.
From the present condition OF the learn what
TO expect on our earth Our planet, full OF ufe
will In $500 100000 years be in extreme old age
These periods OF enormous duration Of time sink into
nsgnihcsnce before the history of the solar system
whole.
We ind wide relation between the parts OF the solar
system that all the planets from the mightest CLONE
smallest satellite. except OF Uranus move in
their paths in the same direction Astronomers would
he much surprised to one OF the asteroids-Of
which 200 have been discJvered-gOng In the opposite
direction rs To see the sun rise IN the west
mighty ai w Whole Bv thu nebuar hypothesis, the
whole solar system enormous mass
n disc Then the outer part became discovered ana
formed orb the next and the next followed. until
there only central left TO rule the entire
Eacn planet went through the same process rings
after rings and satellites after satellites were formed
This nebular theory accounts for the general features
also he considered Professor Newton of
Yale College, estimates that the earth Is
increased by 4OO,OOOOOO every year. 4 his may
amount to Thousands OF tons OF matter, but 1t Is
nothing compared with the mass of the earth.
sun We may say the earth Is growing; bat her
growth only like that of who has already attained
full stature. These met Ors are only the Residue OF
residue the few left out Of the millions of the past In
the earth must have met far more. From
a rough calculation made, find that my assumption
must have been wrong, the eartn would have ILL.,
crca ed cniod more than she did. But we NAV rightly
contend that small part of the mass of tue earth Is
formed from mcteOrc aggregitiOns. III we take
La Places theory with the meteOric.
count for the present condition OF our planet Aud
EARTH anu indeed MI matter kn0w-Our bodies
and brains-Bave down from the heavens, Is IL any
wonder that al higher thoughts and aspirations
are heayenwardl
THE sTEREOPnCoN VIEWS
At this point IN the lecture the lights were turned
out and Professor Proctor explained the stercopiic)n
views thrown upon tine screen In front or the
spectators. The first representation gave rough |
idea OF the solar system as "A DebuiOus mass, |