The enquirer. [volume] (Richmond, Va.) 1804-1815, 1811-10-29

y
ri of Hercules, Id ION. Octant
Sun, esd.
Mercury, God.
Venus, GAL. SON. Asccrtained
MARS, TOd. from cesee-
Jupiter. li7l. tial Globe
Saturn, God
Georgian, gid
Right ascension, 256l
Declination North, SD
Longitude eight Signs, I'd. som.
Latitude North, Old. som.
Amplitude, Sid. SOM NJ
Passage Of the Meridian, sh. lom.
Set II rs night.
Rose As morning.
Progress in its orbit from 5th to goth Oct.
SD. being at the rate Id. AS. 12s. in "A
hours. 0l
Progress in its orbit from 2ota October I'd
being at the rate CT ID. 45m in twenty -fou,
hours.
Inc most striking phenomenon which
comet exhibits is the Tail. Sir Isaac New
ton OBSERVES that there arc three several O.
Pinions about the tails CT Comets Some
Will have IT that they are nothing else but
the beams of the suns light transmitted
through the Comets heads, which they sup
pose to be transparent /; others, that they
proceed from the refraction which light s,f-
fers IN passing from the comets head to the
earth and, lastly, others, that they
are SORT OF clouds or vapours constantly
rising from the comets head, and tending 70
tae part opposite to the sun. The first is
tne OPINION OF such as are yet unacquainted
with optics !; for the beams of the sun are
seen IN darkeaed room only in consequence
OF the light that is reflected from them by the
little particles of dust and smoke which are
Always flying about In the air /; and for that
reason, in air impregnated with thick smoke,
ahose beams appear with great brightness.
and move the sense vigorously in yet finer
ar they appear more faint and are less ca
SHY discerned but III the heavens, where
taere IS no matter to reflect the light, they
can never be seen at all. Light is not seen
IS 1t is in the beam, but as it is thence re-
hected to our eyes; for vision can be no o.
therways produced than by RAYS falling up-
on the eyes, and, therefore there must be
some rejecting matter in those parts where
the tails OF the Comets are seen for other
wise since all the celestial spaces are equal
~ illuminated by the suns light, no part of
enc heavens could appear with mere SPLEEN
bic to many difficulties. The tails of Co
NETS are never seen variegated with those
Colors which commonly are inseparablc
from retracton and the distinct transmits
sion OF the light of the fixed stars ard PIa-
nets to us Is demonstration that the 1ther
or celestial medium is not endowed with any
Ieiractive power: for as to what is alledged
fhae the i,sed stars have beer sometimes
seen oy the Egyfltians environed with
coma or CaEitHtium, because that has but
rarely happeled, it is rather to be ascribed
10 a casual refraction of clouds and so the
radiation and scintillation of the fixed stars
20 the refractions both OF the ewes and air
Tor upon laying Telescope to the eve, those
valuations and scintillatons immediately dis
appear by the trcmulous agitation OF the
III ana ascending vapors, it happens that
tne rays OF light are alternately turned a.
slde from the narrow space of the pupil of
.he eye but no such thing can have place
IN the much wider aperture Of the object
Glass OF Telescope /; and hence it is that a
scinuiiatlon is occasioned in the former case.
winch ceases in the latter and this cessa-
Ton In the latter case is q demonstration of
the regular transmission o. ight through the
heavens without any sensible refraction.-
hut to obviate any objection that NAV be
MADE from the appearing of No tail in such
comets as shine but with a faint light, as if
t1c secondary rays were then too weak to
affect the eyes, and for that reason il is that
the tails of the fixed stars do net a,Dear. we
are to consider, that by the means OF TeIes-
Sopes the light OF the fixed stars may be
augmented above an hundred fold, and vet
no talls are seen that the LIGHT Of the Pa
nets IS yet more copious without any tail
but That Comets are sometimes seen with
huge taiis, when the light of their heads is
but faint and dail."
Slr l. N then proceeds to shcw the phc-
nomena Of the tails # comets must be dcriv-
ed from some rejoicing matter:
And that The tails OF comets do arise
from their heads, and tend towards the
parts opposite to the sun, is farther confr-
inca from the lawS. which the tails observe.
rs that, lying IN Ce planes Of the comets
ORBITS wnch pass through the SIN, they con-
stantiy deviate from the opposition of the
sun towards the parts which the comets
heads m their progress along these orbits
rave LETT. That to spectator, placed in
those planes, they appear in the parts di-
1cctly opposite to the sun but, as the spec-
tator recedes from those planes, their devi
alon begins to appear, and daily becomes
greater. That the deviation, crferis hg,-i-
Oaus, appears less when the tail IS moro oh
hque to the orbit Of the comet, as well as
When the head of the comet approaches
nearer to the sun, especially if the angle of
deviation IS estimated near the head Of the
comet. That the tails which have 10 devia-
ton appear straight, but the tails which de-
VIate are likewise Bonded into certain cur
Vature. That this curvature is greater
wnen the deviation is greater and Is more
sensible when the tall cgteyis ho,,;buo ;e
longer for in the shorter tails the curva-
tnTe IS hardly to be perceived. That the an
PC Of deviation is less near the Comets
lead, but greater towards the ether end NJ