The Jeffersonian. [volume] (Stroudsburg, Pa.) 1853-1911, 1876-01-27
The Life and Death of Worlds.

Prof Proctor delivered the second of
his series Of lectures at Steinway Hall,
\. Y, few evenings ago. His theme
was the Life and Death of Worlds" He
commenced by recapitulating the points
made in the first lecture concerning the
birth and growth Of worlds, and had stop
ped at the epoch of life upon this earth
From this position he advanced to the
general facts concerning all the worlds of
the solar system, claiming that though it
Was not possible to regard them all as alike,
yet that they reSembled each other in GER
tain conditions Of structure, Just as all
animals did in certain things affecting life
There were differences of Il very material
kind between the planets. 1t could not
be doubted that the larger ones must have
been hotter at their formation than the
smaller. 1t was reasonable to assume that
the larger planets Jupiter and Saturn, had
not yet done growing-had not completed
their formation independent of the accre-
tions which they derived from meteors and
other external sources of growth But
besides that probability, there was the
certainty that they must be very much
hotter than the earth, because they not
only had more heat to start with, but part
ed with it more slowly The heat was
given off from the surface, but the internal
heat was out Of proportion to that which
was lost. This had been demonstrated by
making two globes of steel, one four times
the size of the other, then heating them
red hot aud placing them where they might
cool gradually under perfectly equal condi-
tlons. The experiment proved that the
heat contained was in proportion to the
cube Of the mass, while the heat given out
from the surface was in proportion to the
square. Therefore, Jupiter and Saturn not
only had more heat, but cooled more slowly
The diameter Of Jupiter exceeded the earth
twelve times and when it had contracted
to an equal density, having now only
density about equal to that of water, its
diameter would exceed the earth seven
times. Therefore, as the life of world
was confined TO the time when animal life
could be supported upon it, and that de-
pended upon its internal heat, the life of
Jupiter would exceed that of the earth
seven times The earth would be com
pletely denuded of living organisms before
Jupiter took on the stage of life. That
grand planet had not vet come to the cool
ing process, but when it did, the period
would be ten times longer than that of the
earth, which was 320 millions of years.
Though it might be assumed that all the
planets underwent the same series Of epochs,
z ha ahTrip Sf.t ha ha
ing stage, the life stage, and the last one of
death, they were not synchronous by any
means. At this present moment Jupiter
has not yet entered on the cooling stage.
the earth is in the period Of life, Mars of
decrepitude or the last stage Of life, and
the moon is dead. With regard to the
forms of life that have been or will be upon
these worlds, that is a matter of conjecture
purely, the probabilities being that there
would be essential variety. But as regards
the structure Of the plants, it was reason
able to assume from analogy that all were
alike in their elements. The spectroscope
had shown that the elements of the sun
were present in the earth Now, if one
planet contained the same elements as the
central body, the sun, it was fair presump-
tion that all the otheres did also Here
the room was darkened, and the solar
spectrum was exhibited, and after that
prism from the vapor of incandescent iron,
the demonstration being that the vapor of
iron was in the solar body Another slide
presented the planets, giving an idea of
their relative sizes, and this was followed
by one giving the satellites of Jupiter, and
sill another giving the satellites of Saturn.
The Professor said that the life Of planet
depending upon its size, that of Mercury
must be the shortest, as it was the oldest
1t was mooted point which was the
younger, Jupiter or Saturn, but they were
undeniably the youngest Of the solar system.
The eight satellites Of Jupiter presented
singular resemblance to the arrangement
of the planets round the sun, and this
was heightened by the rings which were Il
sort Of zodiacal light. From this point the
lecturer progressed TO consideration Of
the planet Mars which he spoke of in the
period of extreme old age. This he con-
sidered proved by the scanty bottle-necked
seas which were shown by various slides.
These were compared with the abounding
ocean of the earth, and Prof Proctor an
nounced that as the earth parted with its
heat its mighty oceans would assume the
same appearance. This would be done by
the water soaking into the interstices of the
interior when the heat had sufficiently de-
parted to allow of this. From the considera-
tion of this gloomy prospect the lecturer
proceeded to show slides of the moon and
to expatiate upon its desolation. The
lecturer concluded with the declaration that
living organizations having ceased on the
smaller planets would appear on the giante,