The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1856-1888, 1858-10-14
THE PACIFIC
Commercial Advertiser.
On Comefs.

ueouioSity, or tram, which mas the appearance OF III
minous hair. The luminous point near the center o
. comet, which is the most brilliant, is called the nu
eLeus. The haze or nebulosity which surrounds tn
nucleus is called the hair, and sometimes the envelope
and the nucleus and hair combined constitute what i
usually termed the head of the comet. The luminou
tram, extending sometimes to a great distance from
the head, is called the tail of the comet. These bodies
have occasionally appeared in the heavens in all ages
The ancients were divided in their opinion respecting
them; some considering them as wandering stars
others, ss meteors kindled in the atmosphere of the
earth, subsisting for q time. and then dissipated; and
others viewed them as prodigies indicating wars,
famines, foundations. or Pestilencies!
In respect to the tail, or luminous train which
generally accompanies comets, it is found that it is
generally in opposition to the sun, or on the prolonga-
ton of the line which would join the sun and the nu-
eeus. But this is not always the case. Sometimes
the direction of the tail has been found at right angles
with this line; and in some extraordinary instances,
the tails of comets have been observed to point directly
towards the sun. This was the case with q comet
that appeared in 1924, which for about eight days ex-
hibited an additional luminous train in opposition to
that which has assumed the ordinary direction. This
anomalous tail, according to Oilers, was 70 long,
while the other was only 31e, and it was bright
enough to be seen with an opera-glass. In general,
however, it is found that the tail inclines constantly
towards the region last quilted by the comet, as if in
its progress through an ETHEREAL medium, the matter
forming it experienced more resistance than that Of
the nucleus. The tail is generally enlarged in pro-
portion to its distance from the head of the comet,
and in certain cases it is divided into several branches,
as already noticed of the comet of 1907. Some have
supposed that the divided tail is nothing more than
q perspective representation of the sides Of a great
hollow cone; but there are certain observations which
seem TO prove that. in some cases, they have a sepa-
rate existence as independent branches. The most Ie-
markable instance of a divided tail was in the comet
Of 1744 On the 9th and It'll of March, there were
six branches in the tail, each of them about A. in
breadth, and from 30s to 40a long. Their edges were
pretty well defined and tolerably bright; their middle
e1nitted but a feeble light. and the intervening spaces
were as dark as the rest of the armament. The tails
Of comets, as already noticed, sometimes cover an I'M
mense space in the heavens. The comet Of 1850 had
q tail which extended to go, that of 1911 to 230, and
that of 1869 to SO in length; so that some of these
tails must have reached from the zenith to the hori-
zon. The length Of the tail of the comet of 1880, es-
timated in miles, was H., 100000; and that OF 1859,
100000; and that of 1744, s,25o,OOo.
Comets appear to us generally in one of two shapes
one, a glObular mass, as shown in Figure l., on our
next page, which represents Encke's comet of 1928;
and the other, the most general, a roundish mass
with a train or tail attached
In substance, astronomers suppose them to be
vapor or nebulous matter, receiving light from the
SUI, about which they make their eccentric orbits
In the head Of the comet is seen a bright spot, called
its nucleus, and supposed by some astronomers TO be
n substance more solid than the remainder of the
head and the tail. Although the advent of a comet
in our heavens is considered by most people a remark
able event, and in times past occasioned great con-
sternation, their number appears to be very consider
sbIe-over three and a half millions, Arago states.
Many hundreds have been observed; and on an aver
age they appear within our field of observation at the
rate Of about two per year. About two hundred Of
those observed have appeared with sufficient regular
ity to determine with some degree of accuracy their
orbitual movements, and various of the phenomena
Of their existence
Oae of the most surprising points about comets is
their prodigiou5 dimensions The head OF the great
comet Of 1911 was n globular mass whose diameter
measured thrice that OF the sun, or nearly four mil
lion times that of the earth. Its tail was 80 millions
Of miles in length. The space 1t would take up in
the heavens may be gathered from this, that had its
head joined the sun, its tail would still have extended
80 million miles beyond the earth. Suppose the tail
TO have been solid, this comet would have possessed a
bulk nearly six hundred million times that of the
earth. Not less surprising than its volume Is the
speed with which the tail of a comet is sometimes
shot out from the head. The great comet of l843
had a tail 200 million miles in length. This tail was
thrown out in less than twenty days, and If. as IS
supposed, it was composed entirely of matter issuing
from the head. portions of this matter must by some
means have acquired a velocity of not less than 1000
miles per minute
From various observations it is deduced that the
density Of cometary matter is immeasurably less than
that of common air. A body of it many thousand
miles in thickness has no sensible imperfectlon of
transparency, the smallest stars-so small as to be
barely discernible by the aid ola powerful telescope
being distinctly visible through it without the least
dimInution of brightness. The cometary vapor being
visible only as il is illumined by the sun, il is sup
posed that when the comet arrives Mt a certain prox-
unity W luc sun, DOTltDnS pi IulS NdpDI dtttit ~
high a temperature from exposure to the suns heat,
that it becomes entirely transparent and invisible,
just as steam ut the moment of its escape from the
boiler, and before its condensation, is transparent
and invisible. This accounts for the circumstance
that the size Of the head of a comet is apparently
diminished as it nears the sun.
In shape scarce any two comets are alike. Very
often one Of these bodies alters in appearance, to an
extraordinary degree, in n marvelously short time.
Thus Halley's comet appeared on October 8, 1885, in
the most usual form of comets, a body or nucleus
with long flowing tail.
Also, many comets have two or more tails, the
number of these appendices being known to range as
high as six The comet of 1907, had two such tails,
which at various times assumed quite different
shapes.
The comet of IVA had no less than six fully de-
veloped tails. Their edges were splendidly defined.
Their middle was rather feebiy lighted. The space
was as dark as the rest of the armament.
So much of the nature of comets. Their motions
are very eccentric. Their speed is found to increase
largely as they near the sun, and decrease rs they
depart upon their courses through space
Planets near which they pass on their course seem
to attract these nebular bodies, and thus often pro-
duce material alterations in the line of their orbits.
They do not, however, produce any corresponding
in the motions Of the planets, which fact
goes TO confirm the suppositiOn that their matter 10
light and vaporous.
Their periodic revolutions abou. the sun are accom-
plished in very various times-from Eve years, the
Of Messier's comet, to hundreds and even
of years, the periods Of others which have
been observed, and whose orbits have been computed.
IL is, however, an established fact, that at each revo-
luton Of n comet about the sun, it approaches nearer
that lumiuary. And from this some speculative
astronomers have been led to suppose that finally the
comet, succumbing TO the attraction Of the sun, falls
that body; and that comets were, in fact, intend
FL by the Creator as fuel wherewith to feed the fires
Of that illuminator Of darkness. This, however, is
mere superstition Hitherto no one has been fortunate
enough to witness the annihilation of n comet.
Comets have been, in all ages. objects Of apprehen-
to the ignorant and crednlous Scarce any
ssible accident, from the entire destruction of our
zlobe to an epidemic among the cats Of Westphalia,
but these wanderers have been accused Of being likely
% cause, or of having already caused. To the action
" comets are unhesitatingly ascribed extremes Of
,eas or cold, whether general or local; wind and
ain, earthquakes and hurricanes, volcanic e%ruptions,
o1s, foods, droughts, every form OF epidemic disease.