The New York herald., 1874-07-02

to Arago, more than 600, 600 Of them have come
within the orbit OF Uranus.
THE NATURE OF COMETS,
especially or the tail ls . matter Of great uncer-
ta!nty Tne nucleus obeys the laws OF gravity, un-
innenced BY the motions Of the tau. The material
repelled from It, The evident polarity leads to the
natural conjecture that the tail Is electricity ITSELF
Bessel has computed the form OF the tail allowing
eaeh particle 70 move toward by inertia, and by q
repusive force from the sun inversely proper
toned to the square of the distance. The curve
Of several noted comets tails. Professor Peirce,
OF ,a Harvard University, was led by the comet OF
1893 70 the same calculations and results, and pub
hshed them before he was aware that he had been
anticipated by Bessel.
OF primitive ages have IN this century been re-
placed by the unfOunded fear OF the
EARTHs COLLISION
with comet. This was notably the case In 1882
when 1t was predicted that the comet OF that year
would cross the earth's track and great fears were
entertained @ Of collision But there is no evidence
with the earth or any other planet. The motion OF
the earth in It's orbit IS more than 1900 900 miles
come nearer the rruth-remarkable as his calcula-
tons were-than nineteen days In regard to the
all the additional light they possessed, did not
come nearer than nine days Of its temperance
At the point nearest the sun on It's last return In
1885, and as this comet will not return again till
the earth would In its rapid course around the
be within nine days far enough removed from the
influence OF the comet to be out of the way OF all
harm. no Immediate danger Of collision with the
celestial veloc1pede need be apprehended.
THE COMET OF 1858,
called Donatts occupied the attention OF the New
that year. 1t was expected. according to the cal
culati0ns OF astronomers, that It would reach its
eliminating point on the evening OF the 9th of Oc-
tober, and extensive arrangements we're accord
estlng event. Alocal paper thus describes the OBJ
"Heavy looking cumbrous clouds at first almost
overspread the sky. with strong reserve In the
western norizon-symptoms rather unfavorable
examination OF the comet In particular: but lor.
tune, after all, proved favorable. The clouds be-
gan to clear away as the night came on, and by
seven O'CLOCK the prospect was as bright as could
be desired. There, amid bright constellation of
stars, the most prominent object OF them all was
est extent and becoming fainter ana broader as it
reached its extremity, ttll It's dim and uncertain
II was, in fact almost Impossible to see the end Of
It, for there was no distinctly defined line by which
1t could De marked by the eye or even by the tele
The reporter facettously concluded o report Of
ms observations by remarking. as curious
tail, tnat .caudal appendage mas been denied the
dog star"
SCIENTIFIC REPORT.
Harvard University issued an Interesting d0cu,
ment scien tincally describing the event Of 1853
we gather from Its pages that this celestial visitor
Its discovery In June, ana 1t was then travelling at
the rate OF 900 miles an hour This velocity con-
- IKE the sp
sions Of the massive phantasmagorta, Il seemed
day to expand Pa ln bulk as we surveyed its my
10000 miles an hour. exceeding the speed OF the
planet Mercury THIS was at its perlhelion point.
measure OF Its distance from US october II, or some
100000 miles nearer to the earth than 1t ap-
preached the sun. The difference between its
apheon and its perheliOn velocity seems to be the
difference between $50 and $4,000 miles In an
hour. The difference between its remotest and
its nearest solar distance 10 IL PA 600, 900 miles
or nearly eight times the distance OF the planet
Uranus. THIS immense reach, however, would
est fixed star Is billions OF leagues from us. Its
period Of orRital revolution is about twenty or
twenty.fve centuries. The size of its nucleus
1000 miles diameter when about l40 OOO 600 miles
from US, and only 500 miles when Jess than one
deeper at its smaller phase. That nucleus evolved
q number OF luminous envelopes which In aggre-
gate formed beautiful amphltheatre to the spec
glasses the length shrunk to lO0O0, 900 and the
breadth narrowed to 1900 900 miles. Faint stream.
also darted from or Mashed forth occasionally at
an inconceivabe rate Of velocity, sometimes to the
remoteness OF 60 900 miles.
THE ''wAR COMET'' OF 1851
sprang so suddenly upon the people in this lati.
tude, and with such unexamped brillancy and
magnitude, az to astonlsh our scientific men and
gurated, must have something to do with ir, OF
course. But unheraded and uninvited it burst
forth with all Its heavenly beauty demanding
UNIVERSAL ADMIRATION.
On the I'M night Of Of July light haze partly Gov
cred II, but as the night advanced IL grew more
became beautifully defined against the dark blue
OF the sky. the nucleus did not appear
Of that magnitude, according to the description
In the local papers, that many declared it to be,
being only that OF star Of the second magnitude.
1t seemed to attain It's greatest size and bright
preached the nucleus visibly increasing In SIZE
and the tail throwing It's rays still further towards
the zenith The opinion generally expressed was
that 1t was not equal TO Donaus comet while
many considered II the same one on Its return, and
ridiculed the idea OF Its not being seen since 1885,
All surmises were, however, subsequently, set at
rest by the discovery that 1t was
THArCHRRs COMET,
discovered on the Atm Of April 1861, at Mr.. Ruth.
:. Thatcher OF this city. According 10 repors
made At the Cambridge Observatory Only S,
lsdp the comet appears to have passed
its ascending node between the 27tn and 2sth Of
earth then being 277. The inclination OF its orbit
to that OF the earth was SO degrees or very nearly
the greatest possible On the 2Sth OF June the
distance OF the earth from the head OF the comet
and tnat rom the tau considerably less. The
comet sent on its envelopes once day, or four or
hve times THESE concentric arches were conglom-
crate, ana formed hood halo or brilliant bow
over the nucleus Indeed, the halo appeared
an entire circle. II certainly closed In until the
dark axis prevented its further penetration or
progress towards the formation of whole
peIpnery. On the 10th OF October its
length, and sIhibited SPREAD spread of uavs 10000 600
In width Both these dimensions varied
two minutes or two and 0ne-half minutes, but with
gooo glass u was readily recognized. Referring
70 tnls comet Boston paper remarked that al
OF the previous year or TO vhe ever memorable one
OF DOnau In 1858, yet Il was Q large one compared