National Republican., 1882-12-06
A TRIP ACROSS THE SUN
To BE Made To-day by the Planet Venus
How 20 See IL ir the Weather He Fair.

HOW 90 See IL II the weather Be Fhir.
To-day occurs one of the greatest astronomi-
cal events of the century-the transit Of the
planet Venus across the suns disk. Aside from
scientists, there is universal interest in this
phenomenon because of its great practical
value. 1t is hoped to obtain from the observa-
tions which will be made to-day at difierout
points in both hemisphercs definite standard
for planetary measurement. The
"YARp-sTIcK OF THE HEAVENS
is the distance between the sun and earth,
about 81, 100000 miles. Astronomers disagree
as to this distance and the observations to-
morrow are to settle, if possible, a variation
of 100000 miles. The following will mate
rally aid amateurs in their observations:
Venus touches the suns edge at Sh. 55m. a. M;
is wholly ON the suns disk at Oh. 16m. a. M;
begins to leave at Oh. 40m. p. M; and is wholly
off at 3h. ON. The point of the suns edge
at which Venus enters is almost exactly the
lowest, that is, the point which is nearest the
horizon-and during the whole transit Venus
will be well below the center, toward the edge.
1t will pass off at point $50 upward and
westward of the lowest point of the suns disk.
With clear sky any one can observe the
transit, the view being rendered clearer by
the additional use of an opera glass. Venus
will appear on the suns surface as black
dot, apparently about the size of n common
pea, and will seem to move slowly from the
left to the right and upward across the suns
disk.
A REPUBLICAN reporter called yesterday
upon Prof. William Hardness, who has charge
of the observatories at the National observa-
tory, and found him very busy completing
the arrangement of his instruments for
TAING OBSERVATIONS
with telescope, heliometer, and camera. The
telescope and heliometer were in position, and
the final work of placing the photographing
apparatus was in hand. This apparatus has a
focal distance of 38a feet and the images taken
of the sun will be a trife over four inches in
diameter. The image of the sun is reflected
in an unsilvered mirror, and then thrown
through the proper lenses upon the plate.
Delicately. CONSTRUCTED clock-work will keep
the rejecting mirror continually at the proper
angle, following the apparent passage of the
sun. A series of twelve photographs will be
taken every twenty minutes during the tran
sit, if the sky is clear, making two hundred in
all. If the sky is cloudy, photographs will be
taken every time the sun appears. Six photo
graphs can be taken in minute on dry plates.
Prof. Hardness and others engaged in the
work at the observatory were feeling rather
lugubrious over
THE PROSPECT OF BAD WEATHER.
Yesterday afternoon there was a low ba-
rometer center gathering in the Province of
Quebec, and another in the Mississippi Valley,
with a prospect of their spreading so as to
cover large portion, if MOI ali, of the east
ern half of North America.
The transits of Venus occur in pairs, with
an interval of eight years between the two of
each couple and more than century between
the successive pairs. The last transit was in
1874, and after the one to-day there will not
be another until 1904.
At its last session Congress appropriated
5000 for peffecting
ARRANGEMENTS TO MAKE To-DAY's oBsER-
vATIoNs,
and 900 additional to repair instruments.
The commission having the matter in hand
have appointed Prof. Simon Newcomb to take
observations at Cape Town; Prof Asaph Hail,
San Antonio, Texas; Prof. John r. Eastman,
Cedar Keys, Florida Prof. lewis Boss San
tiago do Chilli Lieut.. S. w. Very Santa
Cruz, Patagonia Edwin Smith, New Zea-
| land. Aside from these there will be hun
dreds of private observations made in the
United States by parties rs fully equipped
and as competent as those engaged by the
government.
Great Britain has observers in Canada
West Indies, Good Hope, Natal, Madagascar,
New Zealand, Australia, Mauritius, and the
| Falkland Islands. French astronomers will
view the transit in Florida, West Indies, Mex
leo, Argentine Republic, Patagonia, and Cape
Horn Germany has observers in the Argen-
tine Republic, Falkland Islands, Hartford,
Conn, and Aiken, S. G. Brazil's stations are
at Rio Pernambuco, st. Thomas, and Magel-
Ian Straits. Other countries have various sta
tions in different parts of the world. Over
three millions of dollars will be expended in
these observations.