The Kenosha telegraph. [volume] (Kenosha, Wis.) 1860-1888, 1874-05-21
TRANSIT OF VENUS.
FOR ITS APPROACHING oBsER-
VATTON

VAIION.
vi From the New York Evening Post.
At the end of May or he beginning of
June the first of the parties who are to
observe the transit OF Venus will leave
England for Kerguelen's Land and Rod
riguez. The scientific world--the astron-
omical portion Of it more especially says
the London Telegraph, will watch with
intense interest for their safe arrival with
all their instruments in good order, mas.
much as OH the success Of their observa-
tons in great measure will depend the
determination of the true distance of the
earth from the sun. This problem has
been Zone which astronomers frcm very
early days have been eager to attack.
So far back as tweney centuries ago Arts
tarchus of Samos endeavored TO solve 1t
but with the rough instruments Of those
times he came no nearer TO the truth than
one-twentieth part, Hipparchus and
Ptolemy were also unsuccessful, while
Tycho Brahe, Keplar, and Calico gave
measurements which vary Immensely
from WHAT'S now considered Approximate
ly correct. In the seventeenth century.
however, Flamstead, our first Astronomer
Royal, among others, turned his attention
TO the subject, and from that date con
siderable variation in the supposed di t
ance has been recorded. .a. 6..f..
It is worthy of remark that, as the
mechanical niceties of telescopes and
astronomical instruments were developed,
she sun
HAS APPARENTLY RECEEDEr FROM Us.
The observations recorded during he
transit of Venus in the last century made
as some 95,Oo0,O0O miles away from Ii; but
owing to some unforeseen optical phenom-
no, the figures have been open to pic
ion. More recently the MeasuremAnt OF
the velocity of light by purely mecllan-
icai method, and its application to deter
mine the Suns distance by timing the
disappearance Of Jupiter's satellites, has
caused astronomers to more than think
that 911S millions of miles is nearer the
mark. To settle this question beyond
dispute Git is to be hoped) the present
expeditions has neen organized by the
Admiralty. To the uninitiate this may
seem to be Q but little consequence, cx-
cept as securing the solution of an inter-
esting astronomical problem not worth
the $4,000 or e25,ooO that will be spent
upon it. When, however, it is explained
that this lerge sum of money will contrib
ute to the lessening of the dangers of
navigation by increasing facilities for
obtaining correct longitude in any part
of the globe, the most ardent advocate OF
economy must admit that larger sum
could not represent the true value of the
benefits to be gained. The results OBJ
tanned through the organizing of these
expeditions will hold a prominen: place
in future nautical almanacs. The correct
distance of our earth from Venus is estab-
lished and little reflection will make it
evident that, far away as she is from u.s.
when she passes between us and the sun
(Which she only does at long intervals OF
time), she will appear to cross. at places
of different latitudes, in different paths
At high latitude she will appear to
move much lower down than il observed
at low latitude. II, then, from some
one place of low latitude, and anothe.l
OF higher, Of both Of which the correc
longitude IS known, the respective time
she takes to pass over the SUN be Loted
mathematician will be able to tell us the
real distance she is from as. To Judge
of the accuracy Of observation necessary
for this calculation, it may be Of interest
to state that a# ' #e ssahte a&
AN ERROR OF ONE SECOND IN TIME,
though the total time of passage in some
places will be over four hours, will very
materially affect the results. AT the last
transit the accumulated errors were not
4 !. III {. F4F&E p FL 44
much more, but they were sufficient
to create q doubt az to three
and half millions @5 os miles.
This year the limits on the gas globe
for favorable observation of the phenom-
non lie between the antartic circle and q
parallel ofjlatitude running through the
middle OF Siberia. Unfortunately for US
night shuts ont the Onnortnnitv oc obaer.