The republic. [volume] (Washington [D.C.]) 1849-1853, 1852-11-23
From the Philadelphia Iaquirer.
ThA Mnxu NInnaler MsNleaOa.,.

The New Monster Telescope.
We have already alluded to the fact that an en-
terprising gentleman Of England, the Rev. Mr..
Craig has for some time past been busily enga ged
in constructing, at his own coat, an immense achro-
matte telescope-by far the largest and most
powerful in the world, and from which the most
important discoveries may be anticipated. A late
number Of the London Morning Chronicle devotes
more than a column to the subject. The building
was commenced about four months since, and con,
siss of plain central tower Of brick the walls OF
which are about eighteen inches in thickness, the
height sixty four feet, and the diameter fifteen
feet. II Is erected upon a solid bed of concrete,
and weighs two hundred and twenty tons. This
tower is the very perfection Of construction, as
to prevent the slightest vibration; and this can be
still further provided against by loading the differ
ent floor, by which means the most complete
steadiness 10 secured. By the side of the tower
hangs the gigantic telescope, the immense tube OF
which. measuring SIS feet In length, is shaped
something like a cigar. At one end Ia the eye
piece, at the height of about five feet from the
ground, and at the other the dew cap, covering,
the object of which is to prevent the absorption and
condemnation OF moisture, which takee place dur
ing the night. when the instrument 10 most in
The exterior is Of bright metal, and the interior
painted black, to absorb the divergent rays Of
light. The instrument has a focal distance which
varies from rs to 80 feet, and its greatest circum
ference is l3 leet, the widest portion Of the tube
being about "a feet from the object glass, and
the determination Of this point was the result
Of repeated experiments made with great care.
The instrument has an object ASS OF two feet
aperture, aud has already given evidence Of its
marvellous powers. One OF the lenses Is Of flint.
and the other Of plate or crown glass. The two
placed in contact used in combination, and
constitute the achromatic glass. The tube when
mounted weighs between three and four tons. II
has already been as-ertained that, as a measuring
instrument or for penetrating space, the powers Of
this new continuance are very extraordinary. ''lt
separates minute points Of light go distinctly that
its qualifications a discovering Telescope must
be extremely valuable: 1t resolves the milky way
not simply into beautiful and brilliant stardust,
to use the language Of astronomers, but SUBJ
divides this dust into regular consultations,
showing counterparts of the Orion, the Great
Bear, and the other brilliant galaxies Of
system, adorned, in addition, with the most
ried and gorgeous colors. The lenses are 30 per
fectly achromatic that the planet Saturn ap
pears Of milklike Wilderness; and, as regards this
planet, good deal OF scientific interest has been
recently attached to it in consequence Of the dis
tinguished American astronomer Bond, of the
Cambridge Observatory, Massachusetts,, having
stated he believed he saw a third ring belt
round the planet. Professor Chaliis brought the
upon it, but failed in discovering it. Lord Roses
gigantic telescope was also employed upon it in
vain, and it became a matter Of great interest to
the astronomical world to ascertain whether there
was third ring or not, and this question has been
solved by the Craig telescope, the third ring, OF
clear brilliant gray color, having been distinctly
seen This is owing to the great quantity Of light
which the Wandsworth telescope brings to the eye
pearance to what, in an instrument of less power,
would have been completely invisible.
"Some idea OF it's powers may be formed from the
fact that it magnities the lighto the 40 900
times, and in coarse objects, like the outlines Of
the lunar mountains and the craters, the whole of
these rave may be allowed to pass at to the
focal point, they do not in such objects confuse
it in any appreciable degree In the Craig teles-
cope the moon is q most magnificent object, and
perfectly colorless, enabling the behoderto trace
the outlines Of the various mountain ranges with
such vivid distinctness rs to mako US long for fine
clear weather in order TO bring the whole powers
OF this marvellous instrument to bear upon our
satellite 1t il positively asserted that on iavora:
BILE evening, il there was building object of
the size OF Westminster Abbey in the moon, the
whole OF its parts and proportions would be dis
tinctly revealed. As an illustration of its space
powers, and the manner in which it
grasps in the lights 1t Is stated that after it
was directed to test object, minute speck OF
light in Of the constellation which is not to be
seen at all times by the most excellent instru.
ments, though guided by frst-rate observers, and
in profound darkness. The Craig telescope at once
that this test object not minute
spcck Of light, but brilliant double star. AS soon
as it is finally adjusted, Mr.. Craig proposes to di
rect the instrument to the planet Venus, to ex.
anime it minutely, i'll the hope that he may be able
to settle the question of whether she has satellite
or not"
But, continues the account, wonderful as are the
effects of this telescope il s not yet perfect and it
has been found that a part of one Of the lenses ia
too fiat by about the five thousandth part Of an
inch. TO many it may appear incredible that the
five thousandth part OF an inch can be estimated
30 to be appreciable and measured; but the in
Of portion Of the image revealed the
fact The rays Of light which fall upon that part
Of the lens 90 beyond the focal length and render
the object indistinct and confuse the image. This
portion Of the lens has to be "stopped out' when
accuracy Of definition 10 required;
as, for instance in observing SO fine point as the
third ring Of Saturn; and, as the aperture is 80
large, the absence Of this small portion Of the rays
10 not important, the quantity of light being 80
8 reat. 1t was at fret feared that the attempt to
correct this defect might produce the inconve-
nence of over correcting it, and produce an error
on the other side; but Mr.. Gravatt has Devised
plan by which tho lens, which was polished in the
fret instance by four workmen, may now be re-
polished by machinery upon such exact mathe.
NAUTICAL principles as will prevent the possibility of
error. The machinery is some that similar to that
by which the reflector of Lord Rosse's gigantic
telescope was polished, with the difference that,
the reflector being concave and the Craig lenses
convex, the machinery will act rcverscly.
The Chronicle continues:
"Like Lord Rosse'a great reflector, the achro-
matte telescope on Wandsworth Common can only
calm as we'll clear During the last three weeks,
although succession OF scientific visitors have
been watching on the Common, only one night
proved favorable and that for merely the space of
half an hour. When there is an atmospheric dis
turbance, arising either from high winds or from a
high temperature, during the day, followed ny
cold at night, the objects in the glass seen in
motion, rising and surging like the waves of the
sea. This disturbance, which is seen more or less
in all large Telescopes is owing to the move.
nent of different strata of air, the more heated
portion ascending, and the cold air descending to
supply it's place. The same phenomena are OBJ
servable occasionally even with the naked eye in
hot weather in looking over an extensive beach of
heated sand or dry soil, and the mirage of the
desert and the fata morgana Of the Siclan coast
are to be ascribed to the same atmospheric dis.
turbances.
''The etc upon which the telescope and its tower
stands, aud which is about a mile and half from
The Chaplain station Of the Southwestern Railway,
is Of the extent Of about two acres, and has been
literally granted free of rent by Earl Spencer so
long the telescope ia maintained there. The
ground is at present surrounded by boarding, the
building and its appurtenances being still in the
hands of Mr.. Gravatt and his workmen. 1t is in
tended to erect a small house within the enclosure
for the of the resident observer or astronomer
who may be placed in charge Of the inatrument,
but as the arrangements are nat yet completed,
and the instrument itself not finally adjusted, no
provision has been made 10 enable the public to in
spect this last marvel Of science, which we have no
doubt win sosn become one Of the lions Of the me-
tropolis." .......
We shall await with the deepest intereat the fur
Their discoveries Of this modern wonder OF science.
BARLEY AND MALT,-The former is one Of the
leading articles of grain. the receipts amounting