The Evansville daily journal. [volume] (Evansville, Ia. [i.e. Ind.]) 1848-1862, 1857-05-27

COMETS. Professor Mitchell, prlnci-
pal of Astr ,nomical Observation at Gin
cinnati. delivered public Lecture before
the citizens of that city on THURSDAY
evening on the subject OF Comets. The
following synopsis ofthe Lecture is from
/ the Times.
The lecturer began by taking up the
| probability of collision between the
earth and the comet now TO he seen in the
heavens. and said that he felt no desire
to get around the question at all, hut at
the risk Of destroying all the interest in
the lecture, he would say that there was
not the least probability that the comet
referred to would ever come in COLLISION
with the earth There was more To he
feared from collision with comet never
yet discovered, than from any one whose
existence was known TO astronomers.
lie showed the fixed principl by which
astronomy guided those who were its
students, IN arriving at this conclusion
in regard to all the heavenly bodies, and
Clucidated how by degrees the discoveries
OF certain of the great professor had. sep
by step, rendered those principles iniali
ble. As an eXlmp'e OF the increasing pow
er OF the astronomer in calculating wth
accuracy the movements Of the heavenly
bodies. the lecturer proceeded to show
that the calculation that one hundred and
fifty years ago was considered wonder
iul when it approached within five years
ofa given event, in half that period was
fixed TO within few hours and was
finally arrived at almost to an instant,
at our Ob>erTatory. The facts in con-
nection with the event, as detailed by
the lecturer. were very interesting lie
had made his calculations that at such
il time Mercury would appear on the disc
OF the sun, and five minutes previous
to the computed time hal taken his seat
at the telescope of ;he Mount \ lamS
Observatory to await the event. Dr.
RAY sat at his side. holding in his hand
his chronemeter TO ascertain if the cal
culatlOn had been correct After waiting
what appeared. to the Professor sulii-
Gent period, he turned to his friend and
stated that he must have been mistaken.
No.. replied the Doctor, "you have
scarcely as yet occupied one miaute."
lie III ne again % the telescope and wait
ell patiently ior another period, and then
learned that he had still two minutes in
iavor of his computation. lie again ap
piled himself, and soon after he perceived
t lc disc of the ,uI being slowly cleft
by a small, dark object that annouuccd
10 him that the transit was being made
lie had computed within sixteen seconds
of the exact time. ! hese facts were
only mentioned to show the advance OF
the science.
As yet, however, Astronomy had done
nothing in discovery OF the nature of
comets, save to define the time of their
appearance, and the course they would
Iake In answer To the enquiry whether
comet could strike the earth. he told
them plainly he could not tell. No comet
yet discovered could do so. Bnt he
would a. sure his hearers that no comet !
had yet done 80, nor had any ever inter
ierred with any of the planetary bodies |
lt would require for such an event, should |
we ever live to see it, that we should sur
pass the age Of Methusaleh by about ten
millions ot years.