The Sun.
London, England, 1851-07-11 00:00:00

THE TOTAL ECLIPSE of THE SUN
ON JULY 28.
TO THE EDITOR OF THE TIMES.
Sir,—The aproaching eclipse of the sun on Monday,
July 28, is the only one that will be total in parts easily
accessible from this country for many years to come, and
for this reason it is not improbable many continental
tourists may be induced to locate themselves on the line
of the total phase in order to witness the grand natural
phenomena that occur on such occasions. The more ob-
servers there are the better, and it is a matter of fact
that amateurs have hitherto succeeded quite as well as
professed astronomers in their descriptions and observa-
tions. On this account I beg to send you the following
etunmary of the most remarkable appearances, celestial
and terrestrial, which have been noticed in past years, in
the hope that it may be acceptable to many who have no
opportunity of consulting astronomical works upon the
' subject. I prefix a few particulars relative to the eclipse
of the 28th of this month.
The last total eclipse of the sun visible in London
took place in April, 1715, and there will be no other till
the morning of August 19, 1887. The eclipse of the
present year will be total in the southern parts of Nor-
-lay and Sweden, in northern Prussia, Poland, and Russia;
the principal places within the zone covered by the
moonS shadow being Christiania, Bergen, the well-
known port of Gothenburg, arlskrona, Dantzic,
Nonigsberg, and Warsaw. The eclipse will be more
or less visible to the whole cf North America, the
North Atlantic Ocean down to the thirtieth degree of
latitude, the whole of Europe, and the northern part of
Africa. The total eclipse will commence on the N.W.
coast of North America, near Queen Charlotte's Island,
traversing the continent of America, over the Rocky
Mountains, to the Slave Lake, which will be in
entire darkness at lb. 30 new. Greenwich time.
Afterwards the central line passes over Melville penin-
sula into Greenland, where it arrives at 2h. 5. Hence
it passes north of Iceland, and reaches the coast of
Norway, at a place called Brrekke, about forty miles
north of Bergen, the total eclipse extending at this
time over a zone 150 miles breed. Its after course lies
in the direction of the town of Elbing, near the coast of
Prussia, between Dantzic and Konigsberg, thence
across the south-west of Russia, near Kobrin, in the
province of Grodno, Jitomir, and Ivanovka, to the Sea
of Azov, which will be involved in darkness about 6h.
P.M. local time, while the sun is yet at a considerable
altitude in the heavens.
By a special calculation of the circumstances of the
phenomenon. for Christiania, we find the total eclipse
will begin at.3h. 46m. 3s. Ex. mean time at that place,
end end at 3h. 48m. 475., so that the duration of total
darkness will be 2m. 445. Similarly, by calculating the
condition for Gothenburg, in Sweden, it appears that the
total phase will commence at 3h. 54m. 495. P.H., and end
at 31a. 58m. 7s. local time. At Dantzic the last ray of
the sun will vanish 411. 30m. 555. the darkness
ending at 4h..33m. 595. At Konigsberg this phase will
commence at 4h. 38m. ss., and end at 4h. 41m. 13s. The
sun will be hidden at Bergen 3m. 225., at Carlekrona 3m.
195., and at Warsaw lin. 575.
In.Lonuon about 82-100ths of the sun's disc will be
covered by e
moon,and although some degree of ob-
scurity mus saly take place, it is not_ likely to be
very greht• t:l
Tneces
he gloom, however, is usually of a peculiar
sensibly different from that caused by a clouded
la°6
sky, and if the heavens are overcast at the time, a mist
has' sometimes risen as the greatest phase approached,
teeing the surrounding landscape the same appearance
that we notice, early on a dull October morning. In the
metropolis the eclipse will commence at four minutes
after 2 o'cloCk P. 151, and will end at a quarter past
,4;
the nsiddle or greatest phase will take place at 12 minutes
after &o'clock, and at this moment the sun will appear
as a narrow crescent, having the convex border towards
the horizon:
The progress of a solar eclipse after the first contact
of the moon with the sun's limb is not usually of any
particular interest, even to the astronomer, until a short
tiaie before his, disc is wholly obscured by our satellite.
The diminutibn of light then becomes very marked, and
the dirlsne rapidly deepens as the centres of the sun
and moon 'approach, the final extinction of the sun's
rays being always very sudden. As coon as the total
eclipse has commenced, or, according to some accounts,
a fetv seconds before the narrow solar crescent has
vaninbed, a very beautiful appearance presents itself, in
the form sif a lurniuous cereals, or border of light, which
surrounds the sun and moon during the continuance
of tbe total eclipse, and disappears within a few seconds
of the time when the first returning ray is seen. It
has been described as composed of a circular zone con-
tigueus to the dark border of the moon, and of a
second zone, less luminous, contiguous to the first.
But the. greaternumber of the observers of the eclipse
of July, 1842, do not allude to any second zone of light
further cistant from the moon's l;mb than the brighter
one, the intensity of light appearing to them to dimi-
nish very gradually from the dark border of the moon
until it assimilated itself with the general ground colour
of the heavens. Other observers compare it to the
"glory" with which the painters surround the heads of
saints, divergent rays of light streaming off from the
moon's limb in every direction. Others, while giving
the corona the same general form as before, refer to
certain rays, or aigrettes, as the French term them,
extending beyond the auroleola. The brightness of
the comae varies greatly at different stations during
the same eclipse, according to atmospheric conditions,
and possibly with some regard to the altitude of the
sun and moon above the horizon. In the total eclipse
of July, 1842, the .light was so intensely brilliant at
Lipe.,k, in Russia,- that the eye supported it with
difficulty, and many pentons doubted it the sun had
really vanished. Yet in France and Italy its brightness
was tar inferior; ha light was not strung enough to
throw a perceptible shadow, arid one otnervsr at Padua
estimated its intensity to be that of the full moon as 1
to 7. As might be expecnd, there i, a similar want of
accordance with re;; to the odour of the luminosity
forming the corona. In 1842 skim.; prsr,as, wh9 acre
most favourably situated anti tient r the best atmospheric
eeuii ions, coobiklered it psefectly ehite without the
slightest titles of colour during its continuance. At
Milan is wan straw-coloured, and the astronomers of the
Obstrvatory at Parie, who went to the south of France
to make their observations, agree in giving a yellowish
tinge. On previous occasions it has been described
as pe.art or petch•cotoured, reddish, gold,n yellow, or
presenting the hues of the rainbow. In 1706 it was like
a riig Ori.v.ld at Nuremburg. The breadth has also
been variously estimated. At Perpignan in 1842, the
light of the, corona could be traced to a distance equal to
one-third of the moon's apparent diameter from her bor-
der. AtLipesk, wherait was so 'advantageously viewed,
some of .the rays attained a distance of six or eight lunar
diameters. ,The' efisktronereer Royal 'obsceving at the
Supergi, near Turin, assigned the corona' au angular
dimension of only one-eighth of the moon's apparent
bree,;:he Sdrae ob.lervers have drawn attention to en ap-
parent frthkering nod whirling motion of the corona, re-
semblit.A• th'e ,eff:2ets producsd by certain kinds of fire-
works. At iu 1842, this; luminous ring was in
a state of violent agitation.

But the moot remarkable phenomenon during a total
eclipse, afk:that_ which . most excited the attention
of astronomers in July, 1842, is the sudden visi-
bility of rose-coloured prominences, or "red flames"
as they, ate_ usually called. in different positions. on
the date herder of the moon, and proj,cted cm the
light of ,the corona. :Their aoptartince is-always iostan-
taneous, and the same time, i 3 pretierved as long, as' they
are Nimble. At some places three or more were
seen, in others only two; generally they were perceived
on the northern limb of the moon at distances of thirty
de
grees or upwards from each otticr. M. Arago says
they were of IS rosy tint, but with a yiolet-hue in some
points' (possibly from the' &feet of contrast), and at-
tained an altitude of
(more than one minute of arc from
the moon's lim )th.
b.
ofr astronomers compare them
to the snowy summits units
rising
or setting
sue
_the
Alps illumined by the
th,s anicadrat eiresemblunce was further
strengthened by
and the, absence f At try of the protuberance
etill gPP'arance of scintillation.
Professor Santini, of Peduttit
s;calls them " pyramids of
a
fire," and an observer
,len compares them to
burning coals." Man
in the general reddish ycolo aot
b-ot
ri,tiee, while agreeing
mention the erpliahi or violet ru
h these. prominences,
hues of certain points,
and also record the appearance of a border of rosy
light round a considerable extent of the moon's limb.
August,
Duriog the eclipse of Au
Islands, it
1850, which was total
at Honolulu, in- the eemid..l-,,h
marked,thet the red flames were largest theweaassterren-
limb at the-
Commeneemett of total darkness,o.n but the
gradual]
clerk body' of tho. Moon seemed
more
atoyddirection,
as it advanced across' the sun in an eaYsiteor.covr them
and es gradually to render visible
miosrpere°-k
the re
on the opposite limb.
This flames
eisely jid ieci.eoffee: that ' should be produced, supposing
o f the
them to exist in the upper regions
atmosphere, and the observation consequently very
much strengthens the view taken with respect to the na-
ture Of therose-coloured promincncei. by M. Arago. It
l'lB-, further remarked at .Henelulu . that in the precise
P"point.''ecupied- by the eastern r spot
was visible when thatecho' o the sun's surface was
brou ea
ghti,,ts •.-•.. •R i afterwards by his •--
view kime-day a., axial
rotation. The will add to the interest attaching
to the observations!43 facts -.
(„.., thb approaching eclipse.
The corees, a - '
celestial phtua,:ined led "flames are the roost
cconspicuous
and at the same tiduring
upon the physitul 'tit% e,
b the
a total eclipse co, the sun,
are others which well Bat -
moat iniporPut as bearing
tire-of that laminarY,there'f
much 0,1259,tym.m ftren"erra-attentien tit- the hands o
derateeeltewcese 'Amon Prtel,/iLdell with teleseors of mo.
visibilitpoi Abet contourcbr :Cluny' be , instanced .the
sun's diseitpsief. efeeetbill' ...a-moon which' ie' off the
ev, n bafait rthe)etirt ,tt gitt
(t){? the total phase, and
the appettleteder.6l, flashee ,if **hi the sun -and moon ;
over ttfciefiffsco of our intellite•as tai: eclipse • coloured light
the illtki.fitatinn of solar Spots near eteeliPse progresses;
nieuliailVelpitk of pestles Af e .e —6: WOOn's edffn •
. ...ric,. .µ,.. I.• eer else, as .1 - re- I
blue giFle,iccgt4tkpuFple gradually
towards towards
duke 9 34
with
a the coetees., Al', eiinisicY,gray brighter
2 greettee',Or lees illtitninatien -of-eliee entire. dithe sun;
moon and the. visih s u
ilitY of the spots se of the
pon her ear
flier ; the formation o' , *b:et• are termed "Bail :
beset,," or bright drop, which .h.corae 'visible w,g
e'i;
perei,on oF tin, tan is very
the uneclipsorl narrow,
ie , inirreeietely . before the ceremencement and after
the e,id r,j, tt,:i!'tott4.(erp°, &c. It appears to be highly
desirable ell A the paititiois pi the solar spots should be
determined witli'e.ome degree of accuracy fourteen days
before and :Illy the eclipse, and I will venture to suggest
this class of• obeervation to amateur astronomers who are
~ •,
. . le .means. Those portions of the
tab
providecf teith dui
'.-able
aun'e dilla which present fa ,or streaks of a brighter
part of his surface, should
charectee then the greater
also be notioed. .
As aineady,remarked, the diminution of light is not
usualty very great until about a quarter of an hour before
the cornitetteethent of the natal eclipse. The brighter
planets *ilk-come riei'7l.o to the naked eye, and when
the 4n 1i A ''-ty I , 4 t. a the first and
. 1 l'o,.
_,O lv ‘,1..L 'qtrs. , n or 3 _ . •
IlleColltt
t '3 iVflla,2 e5-' C(jule ino view. In 1842 the
tr"4'.'" ' v.trAck, of stiire perceived without the telescope
was km, it
*i , , ' -it , Moons could distinguish more
::.-.:0,1,0-1 ~, ~.. . . , - ,