National Republican. (Washington City (D.C.)) 1872-1888, 1874-07-22
THE TRANSIT OF VENUS.
1EsWERs TO CORRESPONDENCE RE
SPECTING THIS EVENT.


sIT-HOw OFTEN IT OCCURS AND OTHER
FACTS CONCERNING 1T.
Since our bright, heavenly visitor, the comet,
closed his nocturnal exhibitions Of nebulous
splender, for the purpose Of making more
brilliant display before other spectators Of the
earth, and then disappear in space for ages,
and perhaps forever from the sight OF the
world, the public mind has seized upon the ap-
preaching transit of our beautiful evening and
morning star with considerable enthusiasm and
interest. The transit of Venus will make the
year Of 1874 and the Sth day of December i'm
perishable in the annals Of scientific history,
and is expected to work out greater results for
astronomical calculations than any event since
the discovery Of gravitatiOn by Newton or the
famous formula Of kepler, which has done so
much for the interests Of astronomy.
WHAT DOES TIE TRANSIT MEAN?
The phenomenon above alluded TO is the
passage Of the planet Venus between the earth
and the sun in such q position with REGARD 70
the orbit of the earth that Venus will be seen
by the keen observer in certain parts OF the
world as a small, round, dark spot hitting
across the face Of the sun, az event not hall so
interesting to witness by the ald OF the tele-
scope as are the tagged edges and varying
forms of the solar spots; still the results which
scientific men hope to obtain from this tran
sition will surpass in Importance any astro-
nomical discovery Of the age. This fitting of
the little dark object across the disc of the
sun is called the transit of Venus, the import
ance of which event, in a scientific point Of
view, may be judged from the fact that it af-
fOrds astronomers the best means of meas
uTing the real distances of the heavenly bodies,
and of asCeTtaining their weight and dimen-
sions. 1t makes the passage through this ap-
parent sea Of fire in the space of something
less than six hours, leaving no trace behind,
and producing. so far as would appear to the
casual observer, no appreciable effect Of any
kind. The observations of the astronomer are
to be carefully made during the ingress, tran
sit and egress of the planet, and from the re-
suits Of these observations it is believed that
the science of astronomy will be able to com
Pute the distance and weight Of each heavenly
bO4F which forms part Of cur solar system.
The Arst observation made Of this important
occurrence was through the remarkably devised
plan Of the famous HALEY, whom both the
world of science and letters delight to honor.
While this eminent astronomer was stationed
at St. Helena for the purpose of observing and
cataloguing stars south OF the equator, he took
observations of the passage Of Mercury across
the suns disc, and from the results of his work
he felt satisfied that such an accurate obseTva-
ton and measurement Of the transit of Venus
could be secured that would yield definite
determination of the distances OF the sun from
the earth. He knew that the next transit
would occur in the year l7Gl, but he had no
hopes of living to witness the phenomenon;
nevertheless, in the interests Of science and
progress, he set himself a5siduously at work
performing all the preliminary calculations for
securing, as far as it was possible, the proper
Observations when the time arrived for the
traEsit:Cn.
THE TRANSIT o. 1891.
At the approach OF the transit in December,
17Gl, the scientific world became enthusiastic,
and the Government appropriated liberal aid
and supplies to perfect tho observations in diff
fercEt portions OF the world where the event
was visible One hundred and twenty positions
were selected, and TIE great and important
problem was about 10 be solved, when an IN
forseen difficulty arose, checking the obserya-
tons mGtcriallV, and disappointing many
anxious scientific minds that had labored for
years TO make the event rebound TO the en-
hgGtennCnt and progress Of science. They
hoped to seize the moment Of the contact Of
the two bodies without error, but they were
thwsrted. While the little black orb was sp-
preaching the circular edge Of the suns disc,
and at only two tl.ir-s Of its own diameter
from the glowing surface, dark streak inter
posed itself between the Two objects like a
wedge. Immediately the circular edges OF
both OThs turned or appeared to tatten back.
There seemed TO be a check in the planets
progress, which lasted for twelve or fifteen
seconds duration. Then came M apparent
struggle as Of cOllding bodies, which was fol-
lowed by a sudden spring forward as it were,
and the planetary disc was seen well on
to the suns surface, moving regularly across.
This unfortunate pLeHOGCaOu appeared to all
the Observers, AM rendered the important
calculations Of the G-s:aECc OF the solar orb
from the earth Of great uncertainty.
Again, in 1863, the transit occurred, and as
full and complete arrangements were made as
upon the former occasion, but again, the same
evil appeared, remaining fer twenty seconds.
This made the calculations more uncertain
than before; the result placing the distance Of
the sun at 81, $40, 80 miles from the earth. In
fact, there did not appear to be auy material
Improvement in these observations on Cassinis
estimate Of over a century and q half BEFORE
which placed the distance at 100000 miles.
This phenomenon, it has been maintained, was
due TO an interference OF light in the Observa-
tons and also to the imperfectionin the lenses,
but now It is expected that by a'more delicate
manipulation Of our greatly improved instru-
ments, assisted by the science Of photography
and the power Of the spectroscope, this diff
Guilty will be overcome, and the most import
ant results be obtained.
HOW OFTEN IT OCCURS.
In 1851, as Kepler had predicted, q transit of
Venus occurred, although It was not witnessed,
owing to the want Of proper facilities. This
was followed by another in 1899, which was
observed quite generally throughout Europe,
but owing to the insufficient knowledge Of this
now gigantic science, aud the want Of artificial
assistance, no measures were taken to secure
the great ends for which the Votaries oAastron-
omy are struggling today. The next transit
occurred in l7Gl, rc-OcCuTring gain in 1904
fact which shows conclusively that the transits
Of Venus occur in pairs eight years apart.
There can only be one pair to q century, and it
has been estimated that there will be some CEN
turtles in which no transit at all will happen.
THE COMING TRANSIT.
will take place on the Sth Of December next,
and all that learning industry, wealth aud
skill can do to secure the best results for
science is being done. The different nations of
the world, according 70 their facilities and cir
cumstances, are making preparations to OBJ
serve the transit. Already several expeditions
have sailed for the South Indian ocean and
various other points OF the southern and north
ern continents. Russia will occupy stations to
the number of twenty seven, which will extend
from the KamtsChatka to the borders Of the
Black sea. England has already secured five
stations, and will send individual parties, with
complete equipments, to occupy them. The
for carrying on the work. Germany Is making
extensive preparations, and viii Send four 81
more parties for the special purpose of making
heliOmetrical observations 10 Japan China and
some Of the South sea islands The United
States Government responded literally to the
call Of science by RppTopriating the handsome
sum of $15OOO0, which will enable the COM
mission TO occupy eight or nine different sta
tons, the following parties aud stations having
been selected: d.
Wladivastock. Siberia, Professor A. Hall, U.
s. A: Nagssaki, Japan, George Davidson, U.
s. Coast Survey; Peking, China, Professor
James c. Watson, of Ann Arbor, Michigan;
Crazet's island, South Indian ocean, Captain
RAYMOND, U. S. A: KerZUelan island, South
Indian ocean, Lieutenant Commander George
P. RYAN, U. s. N; Hobart Town, which is the
only satisfactory station in the southern hemi-
sphere, will be occupied by Professor William
Hardness, U. s. N; New Zealand, Professor
c. h. Peters, Of Clinton, New York; this is q
very favorable point. Chatham island, South
Pacific ocean, Edwin Smith, q. s. Coast Sur
Tey, with A. Scott, assistant. Several Of these
parties are under way, in the steamship SWa-
tara, 70 their respective stations, with ample
facilities for making as accurate observations
as the parties Of any other government interest
ed in the great event. The transit cannot be
witnessed in the United States, owing 10 the
relative position Of the earth and sun.
THE NEXT TRANSIT