The Articles
The
Illustrated London News
28 August 1852
by kind permission The Illustrated London
News ©2002
The
Craig Telescope At Wandsworth Common
During
the past three months, the construction of a building on Wandsworth
Common, for the reception of a monster achromatic telescope,
has been rapidly progressing, and is, with telescope itself,
now nearly completed. This great work is under the supervision
of William Gravatt, Esq., F.R.S., or Rev. Mr. Craig, vicar
of Leamington. The site, consisting of two acres, has been
liberally presented by Earl Spencer, in perpetuity, or as
long as the telescope shall be maintained.
Gigantic telescope just erected at Wandsworth Common
The
Illustrated London News ©2002
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As
this gigantic instrument should have some distinctive name,
the various friends of science who have been admitted to view
it have denominated it 'The Craig Telescope' considering as
the Duke of Northumberland's name has been handed down in
connection with the Cambridge refractor - so, also, the originator,
in fact, of this 85 feet focal length achromatic telescope,
with an object-glass of two feet aperture and already capable
of doing marvels, should have his name associated with a work
completely novel in all its parte, and we are happy to add,
entirely of English workmanship. All other achromatic telescopes
of any pretensions are foreign.
The
Duke of Northumberland's telescope is foreign, the Oxford
telescope is foreign, Sir James South's telescope is foreign,
in fact, these instruments were merely purchased by English
money. Not so the present instrument, by far the largest achromatic
telescope in the world.
In
the retired study of a country clergyman, the idea of this
instrument struck him, and having made in his own peculiar
way his calculations the result was a fixed determination
to carry them out, which he has more especially shown in the
choice of his engineer, for many were those he had to reject,
after looking into their plans of mounting his telescope.
He has selected Wm. Gravatt, Esq., FRS, whose name, we believe,
Mr Craig, is more desirous to connect with his wonderful telescope
than his own.
The
powers of this Telescope, as a measuring instrument, are unapproachable
by all others. It separates minute points of light so distinctly
that its space penetrating qualifications will render it,
as a discovering instrument, one of a most superior order.
It resolves the Milky Way, not simply into beautiful and brilliant
'star dust', to use the language of astronomers, but actually
subdivides it into regular constellations. We thus in what
at best was heretofore separated into minute points of light,
can now behold counterparts of our own Orion and Cassiopeia,
our Greater and Lesser Bears and also evidently adorned with
the most generous colours.
The
Telescope is perfectly achromatic; Saturn exhibits itself
with milky-light whiteness. Now that the instrument is adjusted,
Mr Craig wishes the Planet Venus to be examined, for he hopes
to settle the question as to whether she has a satellite or
not, and we need not say what an advantage the solution of
this fact would be to science. The moon is a magnificent object
and perfectly colourless, so that the observer can behold
her mountains and rocks with a vivid distinctness that makes
us long for clear weather to bring the whole of the powers
of this marvellous instrument to bear upon our planet. On
a favourable evening, were such a building, for instance,
as Westminster Abbey in the moon, this Telescope would reveal
all its parts and proportions.
The
central tower is of brick, and 61 feet in height, 15 feet
in diameter, and weighs 220 tons. Every precaution has been
taken in its construction to prevent the slightest vibration,
which can still further be provided for by loading the several
floors, and the most perfect steadiness will be thus ensured.
 By
the side of this sustaining tower hangs the telescope. The
length of the main tube, which is somewhat shaped like a cigar,
is 76 feet, having an eyepiece at the narrow end, and a ducap
at the other: the total length in use will be 85 feet. The
design of the ducap is to prevent obscuration by the condensation
of moisture, which takes place during the night, when the
instrument is most in use.
Its
exterior is of bright metal: the interior is painted black.
The focal distance will vary from 76 to 85 feet. The tube
at its greatest circumference measures 13 feet, and this part
is about 24 feet from the object-glass. The determination
of this point was the result of repeated experiments, and
minute and careful calculation. It was essential to the object
in view that there should not be the slightest vibration in
the instrument, and Mr Gravatt has made the vibration at one
end of the tube neutralise that at the other.
The
ironwork of the tube, which is a splendid specimen of English
workmanship, was manufactured by Messrs. Rennie, under the
direction of Mr Gravatt. The tube rests upon a light wooden
framework with iron wheels attached, and is fitted to a circular
iron railway at a distance of 52 feet from the centre of the
tower. The chain by which it is lowered is capable of sustaining
a weight of fifteen tons, though the weight of the tube is
only three.
Notwithstanding
the immense size of the instrument, it can move either in
azimuth, or up to an altitude of 80 degrees, with as much
ease and rapidity as an ordinary telescope, and from the nature
of the mechanical arrangements, with far greater certainty
as to results. The slightest force applied to the wheel on
the iron rail causes the instrument to move round the central
tower.
All
the optical work has been executed by Mr. F. Slater, of Somer-place
West, Euston-square. The two lenses, one of flint and the
other of plate glass, are thus used: - The plate-glass lens
has a positive focal length of 30 feet 11/2 inch; its refractive
index is 15103. The flint-glass lens has a negative focal
length of 40 feet 101/2 inches; and the refractive index of
this glass is 16308. These two lenses, placed in contact,
are used in combination, and constitute the achromatic object-glass,
the focal length of which is 76 feet to parallel rays –
that is, to all celestial objects.
Wandsworth
Borough News
Friday March 11 1955
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Letters
to the Editor - "The
Scope"
Sir,
You
ask in your comment today for the origin of the name, "The
Scope", for the part of Wandsworth Common where the recent
murder was committed.
View of the moon, February 26, 1852, by John Adams Whipple.
Courtesy of the Harvard College
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The
name is undoubtedly an abbreviation of "The Telescope".
In 1852 a small segment of the Common at the end of Lyford
Road was enclosed and the Rev. John Craig erected there a
brick tower over 60ft high, from the top of which swung a
cigar-shaped telescope, 70ft long with a two-foot object-glass,
swivelling at its lower end on a small circular railway.
Though
it was an imposing landmark it never fulfilled its owner’s
hopes. He was apparently ruined, the building fell into disrepair
and the dismantled telescope was to be seen as lumber in the
builder’s yard in Wimbledon Park Road in the early eighteen
eighties. The ground on which it had stood again became part
of the Common.
A
small water-colour sketch of it is in the Guildhall Museum
and one of my early maps names a small triangular section
of the Common "Telescope".
Further
to your report today that the Historical Society is seeking
illustrations of the Southfields area, it occurs to me that
this district has changed so completely in the last sixty
years that residents might not recognise such pictures if
they saw them. Some idea of what to look for might be helpful.
A
favourite viewpoint was from the top of the Leg of Mutton
Field (now Skeena Hill) across a large pond called The Hollows.
This was before the railway came and, apart from one cottage,
there were no buildings in Granville Road which was a country
lane between hedges, with a stream at one side in wet weather
until you reached the corner where St. Michael’s Church
stands today. Practically everything was hayfields and grazing
land. There should be many sketches and some photographs of
the old Half Mile Road that extended from this corner to Elm
Lodge (now the site of Southfields Station).
Yours
faithfully
E.
P. Olney
122 Kenilworth Court
Putney
SW17
 Bibliography
of J. B. Reade
by kind permission of R. Derek Wood
Advance
of Science, British Association Report for 1854,
Part2, pp. 10-12 item
48a.
from
'Bibliography of J. B. Reade'
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'On
Photographs of the Moon and of the Sun'
Rev. J. B. Reade, M.A., FRS
Abstract:
After discussing a daguerreotype of the moon taken by Bond
in the USA and two calotypes by H. Pollock, Rev. J. B. Reade
reports on pages 11-12 how a group of astronomers, including
himself, at Craig's telescope at Wandsworth used collodion
negatives prepared by Prout and printed by Dr. Hugh Diamond."
see
page 10. see
page 11
History
of Early Photography website at www.midleykent.fsnet.co.uk
The
Athenaeum, 14 October 1854
pp. 1240-1
by J. B. Reade
by kind permission of R. Derek Wood
"[mag-]nifying
power. Dr. Diamond, who printed the positive of the moon,
found the sun picture, however, rather overdone for transferring.
"It will be necessary, therefore, either to use collodion
and nitrate of silver simply without any or but little sensitive
solution or else pass the sun's rays through some coloured
glass, which will partially retard their energy. A series
of pictures of the spots of the sun, as well as of the general
surface, may then be successfully obtained; and hence it is
not too much to anticipate some accession to our knowledge
of the physical character of both our great luminaries by
means of this gigantic telescope, which Dr. Diamond enables
me to exhibit photographically to the [Astronomy] section."
The
above text of Reade's paper read at the annual meeting of
the British Association of 1854 (held that year in Liverpool)
had first appeared with an additional first paragraph in The
Athenaeum, 14 October 1854, pp. 1240-1. In addition a short
mention of this contribution by Reade to the 1854 meeting
appeared in The Art Journal, 1854, Vol. 6, p. 368
Many
years later at a meeting of the Photographic Society of London
(which later became the present Royal Photographic Society)
Reade recalled the use of a yellow filter when taking photographs
with the telescope at Wandsworth. At the meeting of Photographic
Society on 8 December 1868 (at a period when Reade was often
the chairman, although not on this particular occasion, when
the Photographic Society vice-President was in the chair,
interesting for anyone interested in the history of Astronomy
in being the more well-known James Glaisher!) an illustrated
talk had been given by H, Baden Pritchard on ' Photography
in connection with the Abyssinian Expedition'. My Bibliography
of J. B. Reade lists Reade's published remarks as follows:
"item
87. Rev. J. B. Reade, remarks at the Photographic Society
meeting of 8 December 1868, on previous use of a yellow glass
filter to control exposure when obtaining photographs of Sun
through large telescope, Photographic Journal 11 December
1868, Vol 13, p. 187. A slightly different version in the
third person of these remarks also appeared in report of the
meeting in British Journal of Photography, 11 December 1868,
Vol. 15. p. 594"
It
will be noticed in that journal the "large telescope"
is not named, but this does appear in the Photographic Journal's
own report of Reade's remarks:
"...referring
to the difficulty said to have been experienced in limiting
the exposure on certain occasions in consequence of the excessive
chemical activity of an African sunshine, the speaker [Pritchard]
proposed the use of a pale yellow glass placed within the
camera, or adapted to the front of the lens; such an expedient
was successfully resorted to whilst photographing the sun's
disk in the large telescope belonging to Mr. Craig of Wandesworth,
and it would no doubt answer the purpose of diminishing the
intensity of the light when thus applied to an ordinary camera."
R
Derek Wood's "Bibliography of Joseph Bancroft Reade FRS
(1801-1870)" remains unpublished but there is a copy
deposited at the Royal Society Library and Archives: Royal
Society Catalogue R.63128, shelf-mark Tracts X499/3. A printed
copy does also exist at the Royal Photographic Society library
at Bath but the Royal Society copy is what is counted as the
archived source. There is also a PDF file of Part 1 of the
Bibliography available on the Midley History of Early Photography
website at www.midleykent.fsnet.co.uk.
The
Site of the great Craig Telescope at Wandsworth found
by kind permission of Mr Stewart McLaughlin
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The
general history of the very large refracting telescope built
in the 1850s for the Reverend John Craig is well known and
is documented in a variety of contemporary and later sources.
A brief history of this instrument may, however, be useful
and suffice to set the scene.
In
1852 the Reverend John Craig, vicar of Leamington, had a huge
telescope with a 24-inch (610-mm) objective built by Messrs
Rennie under the supervision of a Mr Gravatt FRS. It stood
on a piece of land, provided by the Earl Spencer, just south
of Wandsworth Prison. The large objective lens and all other
optical works were executed by Thomas Slater.
The
75-ft-long (22.8-m) cigar-shaped metal tube was attached to
a 64-ft (19.5-m) high tower by chains, which allowed it to
be raised and lowered. The tower was 15 ft in diameter, weighed
220 tons and had a rotating top to allow radial movement of
the telescope. The eyepiece focusing assembly was mounted
on a wooden trolley which ran on a circular track of 52 ft
(15.8 m) radius.
This
unusual construction was visible to passengers travelling
on the railway line which ran nearby. For the few years of
its existence it was probably as familiar a sight to them
as Herschel’s large telescope had been to stagecoach
travellers on the London road past Windsor in the previous
century.
The
telescope’s objective was not, however, of high quality
spherical aberration was so pronounced that the central part
of the objective had to be stopped out. There is no evidence
that any serious systematic observational work was carried
out with the instrument.
In
1854, Craig’s wife Helena died an in 1858 Craig stopped
using the telescope. The telescope and supporting structure
were subsequently dismantled.
In
1990, having lived for many years in the area, I decided to
try to determine the exact location of the instrument and
to see if any remains could be found.
The
approximate location of the Craig telescope was confirmed
by a visit to the local history library but the original description
of ‘a 2-acre site south of Wandsworth prison was too
vague to identify the actual site. Eventually, however, a
map was found, dated 1862, published by Stanford’s of
Charing Cross, London, which showed an observatory site and
enough detail to match it to modern maps at the corner of
Lyford Road and Routh Road.
A
site visit showed that the area of the common where the telescope
stood is now heavily overgrown. No obvious evidence of any
remains of the tower could be found, although the foundations
to support a mass of 220 tons would be been substantial and
may still exist below ground level.
The
sole remaining (circumstantial) evidence of the structure
seems to be the three iron rail stumps, which are used as
bollards at the northern end of the site at Lyford Road. These
may well have been from the circular track that carried the
eyepiece trolley. The ends appear to be cut for fitting in
a circle and there are only single fish-plate holes, rather
than the two commonly used for actual railway lines. Their
use as bollards at the end of a path suggests they were acquired
locally.
Two
other items of interest emerged from this initial investigation.
Firstly, it would appear that older residents of the area
still referred to the site as ‘Scope corner’ until
quite recently – a nickname which was in general use
until well after the end of the Second World War. Enquiries
also revealed that bricks for the telescope’s tower were
probably fired locally at an area near the common known as
the ‘Frying Pan’. Bricks for Wandsworth Prison were
cast there from 1849 to 1851.
This
is as afar as the investigation has been able to progress
at present. If any members can provide further information
which would help to prove that this area was the actual site
of the Craig telescope I would be very pleased to hear from
them.
S
McLaughlin
Tooting, London
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