The Milan exchange. (Milan, Gibson County, Tenn.) 1874-1978, 1874-06-11

llltN III. Jttl vi dtll lDliONc ltiC to-
tabished precedentS of his party when
he 'vindicateS " them by resolving that
they shall not be remOved.-N J. Tri5-
t01c.
The Astronomical Event of the Century.
Suppose line drawn from the center of
the earth to its surface at the equator /;
suppose another line starting from the eX-
tremity of this latter and continued till it
terminates in the center of the sun. what
is the mathematical expression which ac-
curately describes the angle thus formed
Is it S.92 sec, or is it .03 sec. more or less
That may appeara very abstruse and purely
speculative question to some readers, yet
all the science of navigation, and indeed, all
the results OF applied astronomy, have
sprung from the approximate solution of
this very problem. The slight amount of
uncertainty which still attaches to the an
swer, affects the accuracy of the lunar and
planetary tables of every nautical almanac,
and to a certain degree unsettleS all queS-
tionS of distance in regard to heavenly
bodies. and of longitude in regard to
places on the earth. The solar parallaX is
the scientific name OF the angle whose
character we have roughly indicated, and
the slight uncertainty as TO its true valuc
renders it impossible to say within 100000
miles Just how far we are from the sun.
When the total distance is equal 10 about
81 100000 miles, to approach the certainty
would seem to be near enough for all
practical purposes. But forty times the
earth's diameter is too extensive a depar-
ture from mathematical truth, even in re-
gard to distances so enormous. AstrOno-
mers have, accordingly, set their minds on
reducing this amount of uncertainty to a
minimum of say .0l Sec, 4. G., :he abso-
lutte fixing of our distancs from the sun,
with a margin of $4,000 miles still open to
doubt. Careful observations of the ap-
preaching transit of Venus are the means
relied upon to accomplish this scientific
feat. - .-.... ...
Between the hours of O'Clock of our
time on the evening of December s aud :
O'Clock on the morning of December9, of
the present year. trained observers from
nearly every civilized nation in the world
will, from carefully selected points, be care
fully scanning the passage of the planet
Venus across the luminous disc of the
sun. There has been no such phenomenon
visible from the earth since 1863, and
there will not be another, atfOrding equal
facilities for accurate observations, till the
year 2004. Another transit will indeed
take place eight years hence, but the suns
altitude above the horizon on that occasion
will be too slight to present favorable con-
ditiOnS for observation. As the period of
this years transit occurs during the North
ern winter, the base of observation must
be established for the most part south of
the equator. Points of observation must
be marked off in pairs, because the entire
problem depends on aScertaining with per-
feet eXaCtitude the time at which various
stages of the transit are observed at widely
separated stages on the earth'S surface. In
fact, this method of fixing the angle Ofthe
solar parallaX is simply a working out. on
a colossal scale, OF the familiar geOmetri
cal process Of constructing two sides of a
triangle in order to determine the third.
The largest attainable base of the presum-
ed triangle would of course be the earth's
diameter-lS0 degrees. But suppose two
observers situated this distance apart, and
TO the one the sun Mt the time of the tram
sit would Just be rising. while TO the other
ib would be on the point of setting. For
purposes of observation. however, the sun
must not be lower, in either case, than 100
above the horizon. The easterly observer
must be so placed that the egress of Venus
from the suns disc shall conclude not too
near sunset, and the corresponding Obser-
yer at the west must be able to watch the
ingress of the planet little after sunrise.
OF course this cannot be accomplished
without contraction of base considerably
within the limit of 1902.
The length of this supposed base of the
triangle. whose apex is the sun, requires
in the first place TO be determined with
mathematical accuracy. In other words,
it is necessary to carefully establish, by
lunar observation, what is called the absO-
lutte longitude of each station, and SO to
secure perfect correspondence of astron-
omical time-say within second-as a ba-
sis of observation between corresponding
stations. This OfitSelfrequires some months
of preparation, assisted by instruments of
the utmost delicacv, and for the prelimi-
nary purpose several corps of observtrs are
on the eve of departure from England to
certain desOlate regions of the Antarctic
Ocean selected as the one extremity of the
terrestrial base for the required triangle.
OF course the conditions of the problem
are rather more complicated than can be
briefly and popularity indicated. The rel
ative velOcities of the earth and Venus
must be taken into account: their relative
distance from the sun enters into the cal
culatiOn, so do questions of atmospheric
refractiOn, and other delicate points which
can hardly be briefly indicated without the
use of scientific nomenclature. But this
much can be readily remembered: Venus,
moving faster than the earth, crosses the
suns face from east to west. The most
easterly of two observers, therefore, is the
fist n I,a Hloaly orb of
pletely within the outer rim of the SUMS
disc; in scientific phras e, he is situated at
the point of : greatest acceleration." The
companion observer at the westerly end of
the line sees the same phenomenon some
twenty minutes later, and is said to be at
the point of ''greatest retardation." Let
the exact moment, say of two such critical
points of the transit as the ingress and
egress of the planet on the suns disc be
noted at each station, and the absolute
time interval between the observations OF
two stations be compared with the dis
tance and qualified by the other conditions
to which we have referred, and the much
Sought-for angle will be nearer determine
ton than it is to-day.
England. France, Germany, Russia and
the United States are busily equipping as
Economical expeditions to assist in solving
what has been justly called zone of the
sublimest problems of the universe. /"
Telescopes, equatorially mounted, and
driven by clock-work, so as 10 remain
steadily fixed on the sun after being once
pointed 10 it; photo-heliographs Of the
most delicate construction to present mi
croscopicllly accurate transcripts Of every
phase of the transit altazimuth and tran
sit instruments, which are marvels both OF
massiveness and adjustment-such are
among the articles required for the proper
outfit of each expedition.-Nel0 York
Times. l @
RHUBARB AND DRIED APPLEs.-LOOk
over and. if necessary, wash good dried
apples and put them into a porcelain
lined bottle, with about three parts cold
water. Stew until they are soft enough %
cut with a spoon. Then add as much cut