New-York daily tribune. [volume] (New-York [N.Y.]) 1842-1866, 1858-11-10
Nesp:uork DAILY Gribm,re
NEW PUBLICATIONS.

| THE MATHEMATICAL MONTHLY. November Edited
by j. ID. kuSgLE, NJ, A. s. Cambridge; John Bartlett
The second number of this scientific periodical
amply fulf,s the promise Of its commencement. Ia
addition to copious miscellany of purely mathemati
cal contributions it has popular account of the recent
comet from the pen of Dir. Bond of the Cambridge
Observatory, whose compact and exhaustive expos
ton tempts us to extract the most essential portions
! the article:
! The following account of the Great Comet discov.
cred by Donat the I'd of June 1888 has been pre-
pared Tor The Mathematical Monthly, with the inten-
ton Of furnishing correct information ON subject OF
universal interest," III language freed as lar as possible
from technical expressions The popular character OF
the article renders few preliminary words Of expa-
.ton necessary in reference to the more distinctive
phenomena presented in the motions and physical AS
pect of comets generally:
The first Characteristic Of these singular bodies is
that If their being mainly perhaps in most instances
entirely composed of an il-dehned gaseous or nebu-
ous substance, endowed with properties so extraord-
nary that II scarcely be casscd with matter IN the
ordir airy acceptaon OF the term OF it, extrome at
enuaton and lghtness there can be no question The
planets and among them our earth, must again ana
again have trayersed unframed the tails OF comets.
III October last the debris of the magnificent trn OF
the comet whch has just disappeared from our west
en skies swept over the region occupied by the earth
q few weeks earlier. Instances Of more immediate
proximity Of too common occurrence 10 allow
n, Ia suppose that we are always 10 escape an actual
collision; but it is inconceyable that any disas-
trous consequences could to earth its in
habtants any more than from contact with sunlight
or with tine e,her OF the planetary spaces.
second characteristic is that of internal condensa
ton All comets present this 10 greater less de-
gree. Most of them have q minute steler point,
called the nucleus, which occupies the position Of max
imum density. There are others IN which this latter
feature is wholly waiting. But the number, IN which
il cannot be detected with powerful telescope, is
much smsller than has commonly been supposed. This
center of condensation, or brightest pont, IL, with
exceptions placed on the side which Is near@f ID
the II il always however, very close 10 the Gen.
ter II gravity as is proved by the fact Of it, motion
about the sun, in accordance With the law OF Crawl
taton.
The nucleus itself is a minute point compared with
the immense volume of Ight-giying substance, Of
which il is the controlling center. Whether il is solid
or not is still undecided As far the eye alone IS 10
BE- ted there comets as truly solid as the Plan
cts Themselves In size and weight however,
the true nuclei, apart from their surrounding nebulos-
y are probably quite small, measured by the stand
ard Of the larger PLANETS. Still, il II possible that
there may have been Instances in which the mass OF
these bodies hes been comparable with that OF the
earth anc yet they may have completed their circat
around the Gun, leaving apprecIabe trace OF their
disturbing intuence-the ouly test by which their
could be detected. The evidence, from the TACT
that the smaller stars shine freely even through the
most Condensed portions of comets, adduced by ssro
nomica writer's in proof of their transparency and
by ference, Of their extreme tenuty and hghtness
has certain value when applied to the class OF feeble
telescope comets, but Is scarcely appNcaDie 10 one
Ike that OF the present year, which oyerpowered al
but the brighter stars in the neghborhood Of the nu
cleus by its superior brllisncy.
The feature next in importance to the nuceusi the
train or tail it il usually called although often pre-
ceding the nucleus in ts motion, projected at an I'M
distance from it, aud usually, although BY no
invariably in direction opposite TO that OF tie
sun. The agency of the nucleus in the formation Of
the train, but still in the subsequent control
which il retains il, is one OF the most curious
phenomena presented il nature Often several Of
these sppendages radating at once from the
Iuceus. The greatest variety in curvature OF
outline length, brh ancy and other peculiar tee Is
pre- sented by different comets, or by the same one IN
different parts Of its course. The portions near the
axis are usually darker than the edges, giving at
times the appearance Of C division with stream OF
light on either side.
Tie larger bodies Of this class exhibit wondefiui
complication Of phenomens 10 tie region contiguous
~ the nucleus. OF these the most prominent are Tue
itterposton between the nucleus and the san ot one
weldefined and rounded screens, or eAps oi
dense pebulosity called envelopes, partially out DO.
entirely surrounding the nucleus, and the emission oil
streams or jets OF luminosity bright sectors @c 10
direction inclined opposite TO that OF the tai. "i'h
great variety Of detail IN other respect, the; nave
al sweA-markei tendency TO appear IN tie hFst ~