Vermont watchman and State journal. [volume] (Montpelier, Vt.) 1836-1883, 1843-03-31
MISC ELL A NY.
co NJ Il rs.
From the New York American.-Conc

From the New York Amercan-Concluded
II has been observed that the tail OF a comet is
ALWAYS directed from the sun when approaching
il or going from il. These appearances have made
US believe that the tail of comets is only current
Of yapors elevated by the heat Of the sun, aud
dispersed by the shock of the particles OF light
thrown out by the sun.-vapors which condense in
the region where they are formed These vap0rs,
in dispensing from the centre, have less quickness
than The body, and remain little behind as it the
matter was leaving them the tail experiences
resistance, hut we IRE Ignorant OF the cause which
gives the curve at the extremity of the tail and
this explanation does suffice TO account tor the
strange forms under which comets sometimes pre-
sen, themselves particularly that Of 1744, which
had six tails.
Their proximity to the sun, the continuance Of
the transmission, must render the accumulation OF
heat enormous, and capable of melting and vapOr-
izng all that is in The comet it may even happen
thnt the mass loses its sodNy.
That OF 1850 had 0,006 Tor its perihelion dis
lance, or the Gath of that of Mercury it was l66
times nearer TO The sun than we are the heat thut
it received was $4,000 times greater than that
which the sun communicates to the earth its tenn
perature about 1000 times greater than that OF
melted iron, and ~ 500 times greater than that OF
our summers Ii would need at least so 900 years
to cool this body according TO the physical cir
cumstances in which we live, if il had the size o
our earth and the temperature of melted iron.
With u telescope the tail of a comet is scarcely
visible; this vapor, this fog, has not density enough
to be perceived. The mass itself 10 SO iigh,
substance, that when the comet of 1911 passed
before some star, which is all uncommon event
they pretend to have perceived this through tht
substance of the mass, under the appearance OF
small point. The little telescope comets with
out this mass, and ouly present n cloud less dens'
than The lightest fogs which float in the air.
Comets differ from the planets, not only by thu
Il,n sla
versty Of their movements, which do not have tn
direction from West 10 Fast, nor All orbit n littl
inclined TO the elliptic and little eccentric how
ever, several OF these bodie, have these quaifca
lions.
In general, these orbits are epses excessive
long aud as the GOMEZ is not visible TO US unies
1t is very near 10 the peilheliOn this orbit is yer
much COMPOUNDED with parabola a kind of curry
ed line which is open, and which can be likene
TO an epsis of which the great axis is infinite
When comet appears the astronomers observ
II three times, through paralectic machine, t
obtain the right ascension and decllnalion thrs
poinis OF the curve sufli cling TO determine para
bola, all the course visible and paraboic has bee
concluded upon. Thus three observations eve
near together give the distance OF The periheol
the position OF the point, the epoch OF the passag
and the nodes; from this results the hour OF ii
rising and setting Of the stars which are near
during all the time OF It's appearance.
Near one hundred comets, observed with car
have Their orbits exuctly represented by this curry
in the part visible 10 US thus this fact cannot
doubled.
In The region where we lose sight of the star,
finishes lis immense ehpsis il may even hsppe
that these bodies in fact describe paraboIas or h,
perbolas, aud that they never come near us gal
Buckhardl believes that that Of I77I described
hyperbola The sun occupies the cenIre OF q
these orbits.
To determine upon the movement of a come
II requires us 10 know the seven elements whic
belong 10 the orbit OF u planet and, moreover,
I" necessary to know whether its track he dire