The Middlebury register. [volume] (Middlebury, Vt.) 1850-1882, 1851-08-06
Prediction Of the First Eclipse.
DY PROF. o. MITCHELL.

10 those who have gwen but lItil'
attention 10 the subject, even in our owl
day, with all the aids Of modern science
the prediction of an eclipse seems suf
ficiently mysterious and nnintelligible
How, then, it was possible, Thousands
Of years ago, TO accomplish this samt
grea. object, without any jus, views o
the structure Of the system, seems Ut
terly incredible. Follow me, then
while l attempt 10 reveal the train oI
reasoning which led to the prediction o
the first eclipse of the sun, the mos
daring prophecy ever made by human
genius. Follow, in imagination, hi:
bold interrogation Of the skies to his SOL
itary mountain summit - Withdrawn
from the world-surrounded by his mys.
terious circles, there 10 watch and pom.
der through the long nights of many
many years. But hope cheers him on,
and smooths his rugged pathway. Dark
and deep as is the problem, he sternly
grapples with it, and resolves never to
give over ill victory crowns his efforts
He has already remarked that the
moons track in the heavens crossed the
suns, and that this point Of crossing
was in some way Immediately connect
ed with the coming ofthe dread eclipse.
He determines to watch, and learn
whether the point of crossing was fixed,
or whether the moon, in each successive
revolution, crossed the suns path at a
differen, point. If the sun in his annu-
al revolution could leave behind him a
track of fire, marking his journey among
the stars, it is found that this same track
was followed from year 10 year, and from
century TO century, with undertaking
precision. But il was soon discovered
that il was far different with the moon.
In case she, too, could leave behind her
a silver thread Of light, sweeping round
the heavens. in completing one revolu-
ton, this thread would not Join, but
would wind around among the stars in
each revolution, crossing the suns fiery
track at a point west Of the previous
crossing. These points Of crossing
were called the moons nodes. AT
each revolution the node occurred
further west, until, after cy Gle Of about
nineteen years, it had circulated in the
same direction entirely around the eclip-
tic. Long and patiently did the astron"
omer watch and wait each eclipse is
duly observed, and its attendant circum-
stances are recorded, when, at last, the
darkness begins to give way, and ray
of light breaks upon his mind. He
finds that no eclipse of the sun ever oc-
ours unless the neio moon is in the act
of crossing the suns track. Here was
a grand discovery. He holds the key
which he believes will unlock the dread
and now, with redoubled ener-
gy, he resolves 10 thrust il into the
wards, and drive back the bolts.
To predict an eclipse OF the sun, he
must sweep forward from new moon TO
new moon, until he finds some new moon
which should occur while the moon was
in the act of crossing from one side to
the other of the suns track. This GER
tainly was invisible. He knew the ex>
act period from new moon to new moon.
and from one crossing Of the ecliptic 10
another. With eager eyes he seizes
the moons places in the heavens, and
her age, and rapidly computes where
she crosses at her next change. lie
finds the new moon occurring far from
the suns track he looks around anoth-
er revolution; the place Of the new
moon falls closer TO the suns path, and
The next year closer, until. reaching for
ward with piercing intellectual vigor, he
at last finds a new moon which occurs
precisely at the computed time of the
passage across the suns track. Here
he makes his stand, and on the day of
the occurrence of that new moon, he
to the startled inhabitants Of
The world, that the sun shall expire in
dark eclipse. Bold prediction ! Myste-
rious prophet With what scorn must the
world have received this sol
emn declaration How slowly do the
moons roll away, aud with what intense
anxiety does the stern philosopher await
the coming of that day which should
crown him with victory, or dash him to
the ground in ruin or disgrace. Time
to him moves on leaden wings; day ai>