Middletown transcript., 1872-08-17
The Nature Of Comets.

ly published work on the nature of CON-
cts, makes il his purpose to explain the |
remarkable phenomena they present by an
application Of the established principles Of
phy sioal science alone.
lie starts from the fact that water ,mcr- |
cnry. aud many other substances, even
solids, undergo evaporation to q certain
extent; and he infers from the odors Of
the metals that they also, even a, very
low temperatures. are constantly giving
off vanor, though in an inappreciably
small amount; from which he concludes
that mass Of matter in space will ulti-
matcly surround itself With its own cxha-
la,iors. the tension Of whicl. will depend
upon the gravi,aiivc energy Of the mass
and the existing temperature. IL the nt-
,ractive force Of the body be insufficient to
give the surrounding vapor its maximum
tension for the temperature. the evolution
of vapor will go on until the entire mass
is converted into it, A further analytical
inquiry leads to the result that n finite
mass Of gas in unlimited space is in con-
di,ion of unstable equilibrium. aud mus,
become dissipatcd by continual expansion
aud consequent decrease Of density
and necessary consequence OF this result
is that the space contained in the stellar
universe must be filled with matter IN the
form Of gas
BY assuming, for the purposes Of calcu-
la,ion. that stellar space is everywhere
filled with atmospheric air, and taking the
temperatures ns that Of melting ice. he
finds that Gas in space. at IL lower limi,
OF density, is 50 attcnuatcd tha, mass of
air. which on the enrth's surface would
occupy volume of one cubic dccimeter,
would, when reduced TO this density, ill
sphere of 'nconcciyablc Dimensions; n
ray Of light would not traverse its radius
in a less number Of years than is express.
ed by the numcral ouc followed Us ninety
eight ciphcrs Such medium could have
10 appraciable effect either upon rays or
ligG' ~ The motion 4 bodies
Solid bodies in space must, by virtue
Of their attractive force condense the gas
- as 10 form aa atmosphere on their sur
faces, and the density Il the envelopes can
BE- calculated when ,Lcr size aud mas.
ar known The yale found for the
moon is vanishing quantity, aud per
icc,ly in accordance with the fat that no
lunar atmosphere ,.as ever been detected
For the larger planets, however, the val
u II ygry great, and tin hi4a density Of
their atmespheres mus occasion pereepta-
IL effects upon the Esbt reflected by
them
The temperature of fll mass, exist
ing far from the sun or aus body capable
Il raiiaiing hest 10 il, would BE- that Of
The surrounding space, and il Il s.irsr-
ton were not too great Slow evaporation
would convert il into sphere OF yapnr
Should it, en- the contrary approach the
sun, the heat would cause the whole to be
yaporizel in much shorter time than in
the former case. and the smaller the mass
the shorter tie time would be- The
smaller comets. which often appear like
spherical masses Of yar1r aFe examples of
bodies ef such nature
The seit-luminosity Il comets he sets
down ta electrical excitement, aud ii it
be granted that electricity MAJ be aeyrl.
nped by tie action Of solar heat, in the
process Of evaporation ot tie mechanical
aud molecular disturbances arising from
Y II. u
not only for their sclf.lnmiuosity, but al
So for the formation Of their trains,
He then proceeds 10 d scuss the guam
7 tita,iye difference IN tie eft II eraYta-
/ tie .ni electrical forces upoa ma>srs at
/ distance. and shows TINT, when a body is
/ under both influences simultaneously an
i increase Of the mass results in prrpon-
! ierance If graSitatiou. and sufficient de-
crease of the same, IN prepHndcrancc of
the electrical action llcace the nuclei
+ af comets. as masses, are subject to grav-
/ iin,ion, while the vapnrs developed from
them, which consist. Il very small parti.
clcs. Yield to the action of thn free clcc-
,rieity Of the sun Careful investigation
shows that supposine tie free electricity
! uf the sun to be no greater than ha, be,u
repeatedly observed on The cafih's surface.
il would speedily comm. .ueate 10 sphere
mili,l..e,lrs in diameter ard lan Of a
milligram in seight, velocity Of over
los geographical miles per second. or
such that i, would pas, over a space o.
over 10000, 600 miles in two days The
comet Of 1850 developed in two DAYS a
train Of 60, 600. 900 miles. which is a
magnitude Of the order calculated 1t is
therefore sufficient to attribute to the sun
an electrical energy no greater than that
supposed to account satisfactorily for the
appearances presented by come,ic trains
and it is quite unnecessary to assume the
existence Of some other repulsivc force
When comets appear with trains directed
towards the sun, instead of away from it,
such direction is easily explained b. the
snpposition Of opposite, in place of like,
electrical characters, resulting in attrac-
ton instead Of repulsion.
Professor Iollncr and others think
there is no in,probability Of the existence
in space of fluid masses such 40 described
consisting Of water or Of liquid hydrocar.
bons, and the spcctra Of soue of the neb
ulac aud smaller comets confirm the idea
very strongly.