The Democratic advocate. [volume] (Westminster, Md.) 1865-1972, 1873-05-10
The Coming Transit of Venus.

money 80 that IL would be expended Tor
his benefit.
The Coming Transit of Venus.
Most educated persons know that tran
sits of Venus occur very seldom, and that
they afford, somehow, the means of solving
what great authorities deem the noblest
problem of astronomy, and Of measuring
the distances, dimensions, and weights of
all the host of heaven beyond the moon,
SO far as they are measured at all, ofwhich
the more distant stars are not by any
means yet known. The observations of
transit have to be made in pairs at far dis
tant places to be of any use, and good
many such pairs must be provided for, in
case any of them should fail through
cloudiness or accident. The business,
therefore, is one which States alone can
undertake, and probably all the civilized
nations of the world will take their share
nit There are special reasons for anxiety
that there should be no miscarriage on the
next occasion, Dec. 1874, because it is
certain that there was one on the last, in
1869, and an almost entire failure in 1861;
so that the diameters and distances of all
the heavenly bodies were overrated for
nearly century.
The London Times says =" The first
British position is Alexandria. The French
station themselves at Suez; and the Rus
sian Academy supported by the usual mu-
nifcence Of the Imperial Government when
any worthy scientific object is to be at
tanned, and providing for upwards of 20
stations between Kamschatka and the Eux-
inc, will push observing parties in the
same direction, and occupy stations at
Tihis and near the foot Of Ararat.
The second British station is on the
island Of Rodriguez. The French proceed
to St. Denis de la Reunion while the Ger
mans have fixed upon the Mauritius, and
Lord Lindsay, with scientific spirit
which cannot fail to secure to his Lord
ship lasting honor, is preparing an admi-
rably-equipred expedition for the same
| destination.
"The third British station is Kerguelen's s
Island. The Germans proceed there, pos
sibly, also, making an attempt to effect a
suitable landing on Macdonald Island.
"The fourth special station proposed by
Sir George Airy is Auckland, New Zea-
land. The French Institute places a
party on their nearest possession, New
Caledonia.
"0ur fifth possession is at Woshoo, in
the Sandwich Islands The French pro-
coed to Honolulu, and the Americans, who
confne their attention to stations on the
Pacific, will be in the same region"
A correspondent of Anthony's Photo
graphic Bulletin, writing from London,
says:
"By the indulgence of Mr.. Dallmeyer
received special permission to visit that
part of his capacious works occupied now
for finishing contract orders required by
the British and continental governments.
saw the instruments, 'Photo-heliographs, y
intended for the forthcoming transit Of
Venus. The heliogaph is telescope
mounted for photography, and is about
eight feet long, having an object glass Of
four inches diameter and FIVE feet focal
length, AT the focus is placed an instan-
taneous shutter, acting with quick, sharp
click, as you viii often hear in telegraph
office Through this shutter is an aperture
which, by the simple turn of screw, is
increased or diminished at will. For sun
pictures it is fixed at .O2 of an inch, or to
express it more intelligibly, the opening is
as near as possible the size of pencil mark
an inch and quarter long. Behind this
shutter is placed combination of lenses
corrected for the chemical rays, and the
image passing through is enlarged to four
inches. The size Of the plates used Is six
inches square.
The heliograph is mounted on very
steady stand of iron made portable, that
IS, built up Of several pieces, and finely
bolted together when in use, and is what
is known as an equatorial stand.n The
clock for driving the heliograph is made
TO reverse, thereby suitable for northern
or southern attitudes. As the station for
fixing these instruments had not been de-
fnitely decided, Mr.. Dallmeycr made them
perfectly universal, each one having a
range Of eighty degrees north or south.
The whole instrument weighs about seven
hundred pounds, and costs nearly four
hundred Poands, sterling (say 1000 dol
lars.) The home government ordered Eve
of these instruments; and, beside orders
for India, Russia and other continental
countries, Mr. Dallmeyer has important
private orders in work for the same object. Z"
i
The damsel who was accused Of break
ing young mans heart. has been bound
over in the bonds of matrimony to keep
the pieces