CHAPTER VIII.
ASTRONOMY AND GEODESY IN AUSTRALIA : Part 3.
By Pietro Baracchi, F.R.A.S.,
Government Astronomer of Victoria.
“The Commonwealth of Australia;
Federal Handbook, prepared in connection with the eighty-fourth
meeting of the
British Association for the Advancement of Science,
held in Australia, August, 1914.”
pg.326-390. (1914)
By British Association for the Advancement of Science.
Federal Council in Australia, Australia.
Commonwealth Bureau of Census and Statistics, George Handley
Knibbs
(b) Astronomical Work done in Australia by the Permanent
Government Observatories.
The Parramatta Observatory, though originally a private
establishment, became the property of the New South Wales Government,
and is for this reason placed under this heading.
The Parramatta Observatory.
In 1821, Major-General Sir Thomas Macdougall
Brisbane was appointed Governor of the colony of New South Wales.
Throughout his career as a soldier he had always been devoted to
astronomy, and as the southern heavens offered him almost a virgin
field for exploration, he urged the British Government to supply him
with means for establishing an observatory in the country he was
being sent to govern, but having failed, he undertook to carry out
the idea at his own cost. Accordingly he purchased instruments,
books, and appliances, engaged two assistants, and immediately after
their arrival in the colony, in November, [pg.330] 1821, a site was
selected in close vicinity to his official residence at Parramatta,
upon which a suitable building was quickly erected for the
instillation of the instruments, and by the following April the
Parramatta Observatory was already in full working order.
The assistants were Carl Rümker, an accomplished astronomer
who later became Director of the Hamburg Observatory, and James
Dunlop, whose great natural abilities, especially mechanical,
rendered his services particularly valuable in a place where no
skilled instrument makers were available.
The instruments (4) “were a
transit instrument by Troughton, of 3¾−inch aperture
and 64−inch focal length ; a 2−foot mural circle, with
telescope of the same length, by the same maker; a 16−inch
repeating circle, by Reichenbach; a 46−inch achromatic
telescope, with equatorial motion and wire micrometer, by Banks ; a
clock, by Hardy, set to sidereal time ; and another, by Breguet,
showing mean time.” Also two other
clocks, by Grimaldi and Barraud; a box chronometer, by Dent; and a
pocket chronometer. The programme of the Parramatta
Observatory was principally the determination “of the position of stars down to the
eighth magnitude, between the zenith of the observatory and the
South Pole”(4).
The regular series of observations was commenced on 2nd May,
1822. At first. Sir Thomas Brisbane and his two assistants worked
together harmoniously and with great assiduity, but on 16th June,
1823, Rümker left the observatory, and from that date till
December, 1825, the greater part of the observations were made by
Dunlop.
In December, 1825, Sir Thomas Brisbane returned to England, and
Dunlop followed him towards the end of the following year, after
having continued the work at Parramatta Observatory till 2nd March,
1826, and completed a series of observations of 621 nebulae and
clusters, at his private house, with a reflecting telescope, 9
inches aperture and 9-feet focal length (2) made by himself (5), and
a catalogue of 253 double and triple stars which he observed during
the same period (5)
The records of the observations made at Parramatta with the
transit instrument and the mural circle, from 2nd May, 1822, to 2nd
March, 1826, were placed in the hands of Mr. Richardson, of the
Greenwich Observatory, in 1830 “by
order of the Honourable the Lords Commissioners of the Admiralty,
who directed him to reduce the observations and construct a
catalogue of the positions of the stars” the result being the well-known Parramatta
Catalogue of 7,385 Stars for the Epoch 1825, published in 1835.
The re-discovery of Encke’s comet
at its first predicted return may be justly regarded as one of the
brilliant records in the history of the Parramatta Observatory. The
comet was re-discovered by Rümker on 2nd June, 1822.
After the departure of Sir Thomas Brisbane, the observatory was
taken over by the Colonial Government, on payment of the full cost
of its equipment, to the owner, and placed in charge of Rümker,
who became the official astronomer, and resumed work in May, 1826,
after having, on 15th July, 1824, discovered a new comet —I
1824— which bears his name (10). He made many observations for
latitude and longitude, and observations of the moon, the planets,
and comets. The results are published in the Philosophical
Transactions of the Royal Society, 1829, Part III., and in the
Memoirs of the R.A.S., Vol. III. ; also in Vol. I. of the
Monthly Notices. [pg.331]
At the end of the year 1828, he went to Europe, and some time
after became Director of the Hamburg Observatory. The
Parramatta Observatory remained inoperative for nearly three years.
In 1831, Dunlop returned to Australia, and was appointed
Superintendent of the Parramatta Observatory, which position he held
till 1847.
Most of the work done by Dunlop during this period still remains
unpublished. It is contained in eight books MSS., which were
transferred to the present Sydney Observatory (2).
(7) On 30th September, 1833, Dunlop discovered a comet, and on the
19th of March, 1831, he independently discovered another, which had
been first seen by Gambart, at Marseilles, twelve days before
(8).
The observations of these comets are published in Memoirs of
the Royal Astronomical Society, Vol. 8, page 251 et. seq.
The Catalogue of 629 Southern Nebulae and Clusters, observed by
Dunlop, in 1828, with a 9-inch reflecting telescope of his own make,
as previously mentioned, was presented to the Royal Society, and
printed in the Transactions of 1828, pp.113 and 152, and the
Catalogue of 253 Double Stars, observed in the same year, was
published in the Memoirs of the R.A.S., Vol. III.
After Dunlop’s resignation, the
observatory was dismantled, the instruments packed and stored, and
Australia remained without an astronomical observatory for several
years.
In 1880, when the building which had once been the Parramatta
Observatory was reduced to ruin, fast disappearing, the Government
was induced to erect a permanent monument to indicate the site of the
observatory.
Exactly in the position occupied by the transit instrument, a
marble obelisk now stands, with the following inscription :—
“An Astronomical Observatory was founded here May 2nd, 1822,
by Sir Thomas Macdougall Brisbane, K.C.B., F.R.S., Governor of New
South Wales” (6).
The geographical co-ordinates of this historical point, assigned
to it by Rümker, are Latitude 33° 48′ 50.68″,
Longitude 10h 04m 06.25s.
Although the admitted imperfections of Sir Thomas Brisbane’s astronomical equipment, and his desire to
accumulate data from direct observation at very high speed must be
recognised as the concurring causes which prevented a degree of
accuracy equal to modern needs to be attained in the Parramatta
Catalogue—which represents the main results of Sir Thomas
Brisbane’s enterprise—thus
reducing to some extent the value of the work done by him and his
assistants, we must nevertheless regard that enterprise with profound
admiration and look upon the obelisk now standing on the spot where
Sir Thomas Brisbane, Rümker, and Dunlop observed the stars
crossing the meridian of Parramatta, as the monument raised by an
appreciative generation to commemorate the foundation of Australian
astronomy.
The founder of the Parramatta Observatory and its successive
directors were indeed held in high estimation in England.
The Royal Astronomical Society presented its gold medal to Sir
Thomas Brisbane and James Dunlop on 8th February, 1828, and to Carl
Rümker on 10th February, 1854. [pg.332]
The Sydney Observatory.
This observatory is situated on one of the headlands projecting
into the Harbour, on the western side of Sydney Cove, less than half
a mile from Dawes Point, where Lieutenant Dawes erected the first
Australian observatory, in the year 1788. The locality is now called
Flagstaff Hill.
Through the persistent recommendations of Sir William Denison,
Governor of New South Wales, soon after his arrival in Australia, on
20th January, 1855 (6), the Colonial Government voted a sum of
£7,000 for the erection of an observatory in Sydney, and made
provisions for the salary of an astronomer and a computer.
The Reverend W. Scott, M.A., was selected by the Astronomer Royal,
Sir George Airy, to fill the position of first director of the
proposed Sydney Observatory.
The first duty of Mr. Scott after his arrival was, as he relates
himself, “to fix on a site for the
proposed observatory. For purely astronomical purposes I should have
preferred a position further inland, but as it appeared desirable for
various reasons that the observatory should be in the immediate
neighbourhood of Sydney, I could find no spot more suitable than that
recommended by the Governor on which the observatory now stands.
The building was commenced in May, 1857 and was so far advanced as to
admit of meridian observations being made in June, 1858.”
The first astronomical equipment of the Sydney Observatory
consisted of the instruments purchased by the Government from Sir
Thomas Brisbane. In addition, a complete time-ball apparatus was
installed. By means of this apparatus the ball on the tower was
automatically dropped, at first at the instant of local noon, and
later at the instant of 1 p.m. It was chiefly the practical value of
this service which gave the Government sufficient inducement to
establish the observatory and, at the same time, imposed the
essential conditions in the selection of the site.
The work of the observatory was confined in the first instance to
the approximate determination of the sidereal and thence the mean
time by a number of nightly observations of clock stars (9).
The transit circle by Jones, with which Dunlop had in his later
years made a few observations at Parramatta, had been sent to England
to be remodelled and improved by Troughton, and did not arrive back
till December, 1858. This instrument has an object glass of 3¾
inches aperture and 62 inches focal length. Its circle is 42 inches
in diameter, divided to every 5′ and read by four microscopes
90° apart.
It was completely set up and ready for use in June, 1859.
Mr. Scott complains that this instrument was not entirely
satisfactory. He says (9), “The
instrumental errors are such that although the circle may be regarded
for some purposes as an useful instrument yet it cannot be classed
amongst instruments of the highest order.”
(6) “It was a fortunate
circumstance that just then, in October, 1858, the great comet of
Donati, one of the finest in the century appeared in our southern
sky,” for it served the purpose of
drawing the attention of the authorities to the want of a suitable
instrument at the Official Observatory for the observations of the
comet and of obtaining from Parliament a sum [pg.333] of £800
with which an achromatic telescope, 7¼-inch aperture and 124
inches focal length, made by the celebrated firm of Merz and Sod. of
Munich, was purchased, which was mounted and ready for use in June,
1861.
Mr. Scott remained in office for four years, and resigned his
position on 30th September, 1862. The astronomical work done
at the Sydney Observatory in Mr. Scott’s time was fully published by him in the
four official volumes issued for the years 1859, 1860, 1861, and
1862. These contain the results of upward of 6,600 meridian
observations in both co-ordinates, about 100 transits of the moon and
moon culminating stars, a large number of observations of zenith
stars for latitude, and some observation of comets.
The 7¼-inch Merz equatorial was at his disposal only
fifteen months, during which some attention was given to double
stars.
Mr. Scott published some of his other astronomical work in the
Monthly Notices of the R.A.S., Vols. 19, 20, 21, and 22, as
follows :— Observations of the Solar Eclipse of the Sun, 11th
January, 1861; Comet III., 1860; Comet II., 1861; Encke’s II., 1862; Transit of Mercury N 4,
1861.
The instrumental faults never permitted Mr. Scott to assign to his
meridian observations a degree of accuracy equal to that of the best
observatories.
“It must therefore be borne in
mind” he tells us “that determination of right ascension with
the Sydney transit circle are liable to errors varying from 3.3 to
−4.2 seconds of arc, or 0.22 to −0.28 seconds of time for
a equatorial star.” “An examination of the North Polar distances
leads to a very similar result”
(9),
From September, 1862 to January, 1864, the Observatory was in
charge of Mr. Henry Russell, B.A., who had joined the Observatory as
Mr. Scott’s assistant in 1859.
Mr. Russell confined his astronomical duties to the time service
and to the observation of transits of the moon and moon culminating
stars. He also made a series of micrometric measurements for the
comparison of Mars with neighbouring stars, at the opposition of
1862. This series, however, was not published (6).
Mr. George Robert Smalley, B.A., succeeded Mr. Scott as the second
Director of the Sydney Observatory, in 1864, being selected by the
Astronomer Royal — Sir George Airy — at the request of
the colonial authorities.
It seems that the imperfection of the meridian instruments as
reported by Mr. Scott discouraged Mr. Smalley from undertaking any
serious and systematic work with them, and he resolved to employ them
only for the ordinary requirements of the time service. He devoted
the rest of his time to magnetic and meteorological investigations
and to the initiation of a trigonometrical survey of the colony,
which was then urgently required. Eventually the Government entrusted
him with that work, and operations were commenced in due course for
the measurement of a base line at the south end of Lake George.
Difficulties and delays were encountered in these operations and
the worry “told seriously on Mr.
Smalley’s health, and during the latter
part of 1869 and all 1870 till his death in July of that year, he was
not able to do much of the work which he had determined to carry
out” (6). [pg.334] observation of clock
stars, were some observations of Comet I., 1864, made by Mr. Smalley
with the Merz 7frac14;-inch equatorial, and published in the
Monthly Notices of the R.A.S., Vol.25, p.171 ; and
observations of Comet I., 1865, and of Encke’s Comet at its return in 1865, which were
published in Monthly Notices, Vol.26, p.63.
Mr. Russell succeeded Smalley as third Director of the Sydney
Observatory and Government Astronomer of the colony of New South
Wales.
“Having had a share in all the work
done with the meridian circle, and knowing its imperfections, he
determined to confine the observations with it to those required for
time and longitude, and at once urged the necessity for a new
meridian instrument” (6).
The approaching transit of Venus gave him the opportunity of
obtaining the sympathy of the Government for the acquisition of more
instruments.
The astronomical operations which figure more prominently in the
history of the Sydney Observatory during the first seven years of
Russell’s regime are the preparations
made for observing the total eclipse of the sun in December, 1871, in
the extreme north of Australia, and the transit of Venus in 1874, of
which a brief account will be given in another part of this
article.
To the ordinary routine of observations of clock stars were added
observations of the transit of the moon and moon culminating stars
for longitude, and the observations of Herschel’s Cape Catalogue of Double Stars.
A remarkable feature of this period is the increase of
instrumental power which Russell, by continuous effort and
determination, succeeded in securing for his observatory.
In 1872, with the assistance of the Royal Society of New South
Wales, he obtained from the Government a sum of £1,000 for
instruments, the greater part of which he used in procuring an
achromatic object glass, 11.4 inches aperture, and 12½ feet
focal length, by Schroeder, of Hamburg, for which he designed and had
constructed in the colony under his supervision an equatorial
mounting provided with all the requisites of a modern instrument.
This instrument was installed in 1874.
In the same year the necessity having arisen for the determination
of star positions with the greatest possible accuracy to serve the
purposes of the trigonometrical survey of the colony of New South
Wales then in course a sum of £1,000 was granted by the
Government for the purchase of a high-class transit circle for the
observatory ; Mr. Russell ordered the instrument from the firm of
Troughton and Simms, and procured also a large eighteen-prism
spectroscope, by Hilger, and other apparatus.
The new transit circle has an object glass of 6 inches clear
aperture and 85 inches focal length. It has two circles graduated to
every 5′ read by four microscopes ; regular observations with
it were commenced in February, 1877.
The instrument was employed for observations of stars required in
the operations of the trigonometrical survey, and of other stars near
the zenith, of which it was intended to make a special catalogue.
[pg.335] “In fact, since 1870, the
observatory has been entirely refurnished with instruments of the
most modern and perfect forms, and, although they are not equal in
size to some of the giant telescopes which have been recently erected
in Europe at enormous cost, they are quite equal in quality to those
in the best European observatories, as is proved by the observations
now made with them.” Thus Russell wrote
in 1882 (6).
An important series of meridian observations of Mars at its
opposition in 1877 and comparison stars had been obtained by Russell
with the new transit circle “for the purpose of determining the
solar parallax. A long series of observations was made which,
combined with observations made at Washington, gave 8′.;885
inches as the value of the solar parallax” (6).
The results of the work done with the transit circle up to the end
of the year 1881 are published in two volumes, “Sydney Observatory — Astronomical
results for the years 1877-78 and 1879-1881.” These results were used by A. Stichtenoth
to form a catalogue of 1,543 stars for the epoch 1880, published in
Veröffentlichungen des Königlichen Astronomischen
Rechen-Instituts zu Berlin, No.20.
The results of observations on double stars are published in a
separate volume, Sydney Observatory — Double Star Results,
1871-1881.
In the first volume of astronomical results is shown a summary of
the observations of transits of the moon and moon culminating stars
made by Russell in the years 1863, 1871, 1872, 1873, and 1874, from
which is derived the value of the longitude of Sydney (according to
Russell), 10h. 4m. 50.81s., which was adopted till 1883.
During the eight years after 1881, the same routine of meridian
observations and observations of double stars were continued.
The double-star work of the years 1882-1889 was published in
Memoirs R.A.S., Vol. 50.
In 1887 Mr. Russell went to Europe to attend the Astrophotographic
Congress at Paris, and on behalf of his Government and the Government
of the colony of Victoria, pledged the Sydney and Melbourne
Observatories to undertake a share in the astrophotographic programme
which was decided upon by that Congress.
The part of the sky allotted to Sydney ranged from 57° to
61° of south declination, and that of the Melbourne Observatory
from declination −65° to the South Pole.
Russell obtained his photographic object glass from Steinheil, of
Munich, and had the mounting, with all requisite accessories, made in
the colony on his own design, and under his personal supervision. He
had a circular wooden observatory detached from the main building,
built for the special purpose of housing this astrophotographic
telescope.
The mounting of the astrograph was ready in 1890, but the object
glass did not arrive till later. Russell, in the meantime, mounted a
Dallmeyer portrait lens 32 inches focal length and 6 inches aperture,
and, finding this star camera to the tube of the astrograph, employed
it in taking a scries of highly successful photographs of the Milky
Way. These photographs, seventeen in number, accompanied by a
description of each, form an album which was published in 1890.
[pg.336]
The installation of the new object-glass was completed in 1891,
and the work reached the end of the preliminary experimental stage in
1892, from which time it proceeded regularly in succeeding years till
1898.
In 1889 powerful street lamps and electric lights were placed in
the vicinity of the Observatory, the effect of which was to interfere
so seriously with the work of the astrograph that it became necessary
to remove the instrument to some better locality.
Accordingly, the Government, having granted a piece of land for
this purpose at Pennant Hill, some 11½ miles to the north-west
of Sydney, and 615 feet above sea-level, a suitable building was
erected, and the instrument installed there in 1899, where the
astrophotographic work has since been carried out by Mr. Short, as a
branch of the Sydney Observatory.
For the last 22 years the determination of the places of reference
stars to be employed for the reduction of the plates of the
Photographic Catalogue, and actual photographing of the regions
comprised in the Sydney zones, constituted the greater part, if not
the whole, of the astronomical programme of the Sydney Observatory,
the results of which have not yet appeared.
During this long period observations of double stars were
continued, the results of which have been published in various lists
in the A.N., Nos. 31.54, 3240, 3303, 3369, 3423.
Many other observations of an occasional character were made, and
other astronomical duties performed, which come within the scope of a
national observatory, but it would be impracticable to give here a
detailed account of them.
Russell, who died in 1907, may be regarded as one of the principal
factors in the advancement of Australian astronomy during the last
half century. In estimating the value of his work, it must be
remembered that by far the greater part of his energies were expended
on the development of Australian meteorology.
He was the inventor of no less than 23 instruments, and the
contributor of some 130 papers to various scientific societies. He
was made F.R.A.S. in 1871, F.R.S. in 1886, C.M.Gr. in 1891, also, in
the same year, Vice-Chancellor of the Sydney University, where he
graduated in 1858, and President of the R.S. of New South Wales for
some years.
After Russell’s death, Mr. Alfred
Henry Lenehan was appointed Government Astronomer. Under him the
astronomical work of the Observatory was a continuation of the
routine programme of previous years, which he was bound to accept and
to advance as speedily as he could, under the administrative
difficulties of the time, till completion might be reached.
He died on 2nd May, 1908 ; and till August, 1912, Mr. W.E. Raymond
remained in temporary charge of the institution.
In August, 1912, Mr. W. E. Cooke, M.A., formerly Director of the
Perth Observatory, was appointed Government Astronomer of New South
Wales, and Professor of Astronomy in the Sydney University
In his report to the R.A.S., M.N., February, 1913, No.4, Vol.
LXXIII., we read—
“Owing to the rapid growth of
Sydney, the present site of the Observatory has become unfit, and the
instruments are not suited for the exacting requirements of modern
astronomy. It has therefore been determined to [pg.337] move the
entire institution to a new site, and to provide some new instruments
and remount others. In particular, a new meridian instrument of
modern design, suitable for fundamental work of the highest
precision, will be provided in accordance with the recommendation of
the Paris Astrographic Congress of April, 1909.
“Meanwhile the routine work has been
almost stopped for the present, and preparations for the
reorganisation have been commenced.”
The Williamstown Observatory.
E. L. J. Ellery was appointed, in 1853, by the Government of the
Colony of Victoria to establish a small observatory at Williamstown,
chiefly for the purpose of determining time and supplying a daily
time signal for the service of ship masters.
On taking up his position, Ellery found the following preliminary
arrangements already made :
A time ball apparatus already installed on a tower at
Point Gellibrand, with the requisite apparatus and machinery for
hoisting and dropping the ball.
Some astronomical instruments, including a transit
instrument on order in England.
A site for the Observatory selected.
A sum of £2,800 voted by Parliament for the
erection of a suitable building.
Under these conditions he set to work in a wooden hut, using a
sextant and a chronometer, and the first time signal was issued in
August, 1853.
Such was the beginning of the Williamstown Observatory. The
geographical position of the place had been determined some years
previously by Captain Stokes, of H.M.S. Beagle, his values being
— Latitude 37° 52′ 52″ S. Longitude 9h. 39m.
42s. E.
In 1854, the instruments on order in England arrived. They were a
25-inch transit instrument and a high-class astronomical clock, by
Frodsham. A more ambitious transit instrument, which had been ordered
from the firm of Troughton and Simms, arrived in 1855. This was an
excellent instrument, with an object glass of 3½ inches clear
aperture and 45 inches focal length.
In 1858, the geodetic survey of the colony was decided upon, and
placed in charge of the astronomer. The proposed scheme was to divide
the country for purposes of land settlement by meridians and
parallels, the primary lines being first located at distances of
1°.
The Observatory having by this time acquired national importance,
on account of its public duties in connexion with the geodetic survey
and time service, the Legislature passed a resolution on 8th
December, 1859, according to which a Board of Visitors to the
Observatory was appointed by the Governor in Council on 30th January,
1860, the Governor (Sir Henry Barkly) becoming himself chairman of
the first Board.
A new circle arrived in August, 1861. It was constructed by
Troughon and Simms. Its object glass has a clear aperture of 5 inches
and a focal length of 72 inches. The circle is of gun metal, 4 feet
in diameter, divided [pg.338] to every 5 minutes, and read by four
microscopes attached to one of the two stone piers which support the
instrument. Observations with this instrument commenced in October,
1861.
A new clock, also by Frodsham, had arrived a year before, and
still more instruments were acquired in this and in the following
year. These were a chronographic apparatus, by Siemens and Halske, of
Berlin ; an Airy zenith sector ; and an achromatic telescope,
equatorially mounted. This latter instrument, by Troughton and Simms,
has an object glass of 4½ inches clear aperture and a focal
length of 5 feet ; with it a valuable series of observations of Mars
at its opposition of 1862 was obtained for determining the parallax
of the sun in connexion with other observatories.
In 1853 the site occupied by the Williamstown Observatory seemed
quite suitable for an observatory, but the rapid growth of the
community, the construction of a railway terminus and large railway
workshops near it, had in 1862 rendered its position unfavourable, in
consequence of which it was decided to remove it to Melbourne.
Since 1857, there had been in existence a meteorological and
magnetically observatory, which was established and conducted by
Professor George Neumayer. This observatory was situated at Flagstaff
Hill, at the west end of the city of Melbourne. In 1863, Professor
Neumayer, having decided to leave Australia, it was arranged that bis
observatory should be amalgamated with the new Astronomical
Observatory.
The building for the new Observatory was commenced in 1861 and
completed in 1863.
In June of that year the Williamstown Observatory was dismantled,
and “the whole of the instruments and
appliances removed to the new building now known as the Melbourne
Observatory” (11). The results
of the work done at the Williamstown Observatory are published in the
volume entitled — Melbourne Observatory. Astronomical Results.
1861-62-63.
This volume contains the Williamstown catalogue of 546 Stars for
the epoch 1860, which at the time it appeared received warm
appreciation from European and American astronomers. Also a series of
right ascensions and north polar distances of the moon, extending
from January, 1861, to 7th October, 1862, upon which rested the
longitude of the Williamstown Observatory ; and finally, the series
of observations of Mars and comparison stars during the opposition of
the planet of 1862.
The Melbourne Observatory.
This Observatory is situated at a distance of 4 miles north-east
from the site of the old Williamstown Observatory, and about 1 mile
south-east from the centre of the city of Melbourne, within an
enclosure of 4½ acres of land permanently reserved for
observatory purposes in the Domain Park.
In addition to the main building, which provided ample
accommodation for the astronomical instruments of the Williamstown
Observatory, special structures were erected for the magnetic and
meteorological instruments which were taken over from Professor
Neumayer’s Flagstaff Hill Observatory.
[pg.339]
The Melbourne Observatory was ready to commence work at the end.
of June. 1863, its astronomical equipment consisting of the
instruments removed from the former Observatory at Williamstown.
For nearly three years the work consisted almost entirely of
meridian observations of the fixed stars which were employed in the
operations of the geodetic surveys then in course in Australia and
South America. A catalogue of these stars was prepared each year and
printed in due course.
In 1862 the Royal Astronomical Society initiated a movement for
carrying out by British effort a southern durchmusterung on the same
basis and the same scale as that which Argelander was conducting for
the northern hemisphere. The idea was to obtain the co-operation of
the three southern observatories — Madras, Cape of Good Hope,
and Melbourne.
The Melbourne Observatory offered to join in the work, and was
eventually allotted the zone from 60 degrees to 80 degrees of south
declination.
The undertaking involved the determination of the positions of all
the stars comprised in this southern belt down to the tenth order of
magnitude.
This work was commenced on 11th April, 1866, and continued for
about six years, when it had perforce to be discontinued. Its results
comprise the mean places for the epoch 1875 of 48,672 stars down to
the 9th, and in many instances the 10th order of magnitude, in the
zone from 65 degrees to 69 degrees of south declination. These places
are roughly arranged in the MS. in order of right ascension, the
right ascensions being given to the nearest tenth of a second of
time, and the north polar distances to the nearest second of arc,
showing that the work aimed at a somewhat higher accuracy than that
of other works of this class, such as Argelander zones or the
C.P.D.
With very little labour the work can be arranged and prepared for
printing if means be provided for the purpose.
In the year 1850 a memorial was presented to Lord Russell, the
object of which was a request to Her Majesty’s Government to establish “;a powerful reflecting telescope (not less
than 3-feet aperture) in some fitting part of Her Majesty’s Dominions, and for the appointment of an
observer charged with the duty of employing it in a review of the
nebulae of the southern hemisphere.”
The opportunity of enhancing the importance of the Observatory by
the acquisition of a great reflecting telescope was quickly
recognised by the Board of Visitors, and His Excellency the Governor
(Sir Henry Barkly) was requested to obtain “an expression of opinion from scientific men
in England as to the importance of the results to be expected from
it, the most suitable construction of telescope for the purpose, both
as to the optical part and the mounting, its probable cost, and the
time requisite for its completion.”
“An application was made through the
Secretary of State for the Colonies to the Royal Society of London
for their opinion, and the President and Council of that body, after
a very full consideration and a long correspondence with the most
eminent practical astronomers of the day, recommended — (a)
That the telescope be a reflector, with an aperture of not less than
4 feet ; (b) That the large mirror be of speculum metal ; (c) That
the tube be constructed of open work and of metal” (12). [pg.340]
The instrument was completed in 1868 and was sent to Australia,
reaching Melbourne in November of that year ; it was ready for work
by the end of June, 1869, and the observations commenced in August of
the same year.
Grubb’s 4-feet reflector has, since
its installation, been styled “The
Great Melbourne Telescope.” An
admirable description of it by the late Dr. T. Romney Robinson, D.D.,
F.R.S., appears in the Philosophical Transactions of the Royal
Society of London, 1869, page 127 (13).
The telescope itself is of the Cassegrainian type, and is mounted
equatorially in a somewhat similar form to the Sisson ; “its declination axis being placed between
the upper and lower pivots of the polar axis, which run in large
bearings, supported by two distinct massive stone pillars rising from
a solid bed of masonry. The R.A. circle clamps and slow motion
apparatus are between the declination axis and the lower pivot. The
declination circle is fixed to the bearings of the declination axis
on the side of the polar axis, opposite to that of the telescope” (13).
The dimensions of the optical parts are as follow :—Aperture
of primary speculum, 48 inches ; focal length of primary speculum,
360 inches ; aperture of secondary speculum, 8 inches ; focal length
of secondary speculum, 74.7 inches; equivalent focal length, 1.994
inches.
There are two large 4-feet mirrors, each mounted in its cell ready
for attachment to the telescope, floating on a complicated support of
48 cups and balls connected to the ends of arms which form a series
of triangular levers, and upon hanging rings around its
circumference. These mirrors have a central circular opening of 8
inches in diameter to admit the passage of the cone of rays from the
convex secondary mirror to the ocular. The mirrors, both primary and
secondary, are of speculum metal.
The tube of the telescope consists of three portions. The lower,
or “eye end” position consists of the cell carrying the
large speculum ; the central portion is a cylinder of boiler plate,
about 93 inches long, to which is attached the declination axis by
means of a massive cast-iron cradle and strong iron bands embracing
the cylinder. The speculum cell fits to the end of this cylinder on
turned surfaces, and is held to it by three strong screw-bolts.
The upper portion of the telescope tube is made of open steel
lattice-work, about 20½ feet long, fixed by turned flanges to
the boiler plate cylinder by bolts and nuts.
The secondary mirror, in its cell, is mounted in the centre of the
lattice tube, about 300 inches from the surface of the primary
speculum and 39 inches within the object end of the tube, and means
are provided to enable the observer while at the eye end to alter
this distance for focussing.
The polar axis is 123 inches long, and its two pivots are 12
inches in diameter. The declination axis has a diameter of 22 inches
at the bearing near to the telescope, and 9½ inches at the
counterpoise end. The circles are divided on silver bands, and have a
diameter of 30 inches.
The driving clock is governed by a double conical pendulum of the
well-known “Grubb” form. The direct driving weight is 260
lbs., and the total weight of the moving parts is approximately
18,000 lbs.
The instrument is provided with an achromatic telescope finder, 4
inches aperture, seven negative or Huygenian eyepieces ranging in
power from [pg.341] 234 to 1,000, a parallel wire micrometer, a
spectroscope, and a camera for photographing telescopic images at the
focus of the primary mirror, the secondary mirror being removed when
the camera is used.
In 1910, a Voigtlander portrait lens of 6 inches aperture and 40
inches focal length, for which a metallic mounting was made at the
Observatory, was attached to this telescope.
The great Melbourne telescope was for many years after 1869
employed in the revision of the nebulae and clusters which were
observed by Sir John Herschel at the Cape of Good Hope in the years
1834-38, and the results obtained are as satisfactory as the
committee of the Royal Society of London, on whose recommendation,
supervision, and approval the 4-feet Cassegrain was constructed,
could have expected.
Most of Sir John Heischel’s southern
nebulae have been examined, and many hundreds of drawings of these
objects, with notes and micrometric measurements, exist at present in
the observer’s note books and registers
; but there has been no opportunity since 1891 of arranging this
material for publication.
In 1871, an expedition to the extreme north of Australia was
organised for the observation of the total eclipse of the sun in
December of that year, in which the Melbourne Observatory took part.
This expedition is referred to in another division of this paper.
In 1874, the occasion of the transit of Venus, which occurred in
that year, gave Ellery the opportunity to add to his observatory
equipment a photoheliograph, by Dallmeyer, with object glass 4 inches
aperture and 60 inches focal length ; an achromatic telescope, 8
inches aperture, 110 inches focal length, by Troughton and Simms,
mounted equatorially and provided with all requisites for micrometric
measurements and work of the highest precision ; also another
equatorial telescope, 4½ inches aperture and 60 inches focal
length, by Cooke and Sons, of York.
The preparations for observing the transit of Venus included the
dismantling of the east transit telescope of 6½-inch aperture,
with which the Melbourne zones had been observed till 1872. For this
telescope an equatorial mounting was constructed at the Observatory,
and the instrument has since been used for expeditions as a portable
equatorial.
Two new barrel chronographs were also constructed at the
Observatory.
After the transit of Venus, it became a part of the daily routine
to take a photograph of the sun in the forenoon, which was done on
all available opportunities for more than 20 years.
In the time which elapsed between the two transits of Venus of
1871 and 1882, the routine astronomic;al work of the Observatory did
not suffer any marked changes or interruptions.
Stellar photography was tried with the great telescope, but
unsuccessful1y. It was not found practicable to guide the telescope
steadily enough during exposure. Photographs of the moon with the
great telescope, which only required an exposure varying from 1
second to 3 seconds (with wet plates) were, however, successful, and
they were even considered at tho time amongst the best that had ever
been obtained.
The photographs of the moon obtained at the focus of the primary
mirror were 3½ inches in diameter. [pg.342]
The pictures of the sun obtained with the photoheliograph were 4
inches in diameter. One thousand seven hundred and twelve of these
pictures on glass were sent to the Greenwich Observatory and the
Solar Physics Committee in England, for measurement and tabulation
(14).
The preparations for the transit of Venus of 1882 and the
observations of that astronomical event in this State will be dealt
with under another heading.
The determination of the difference of longitude between Port
Darwin and Singapore, and between Port Darwin and the Australian
observatories, which were undertaken in 1883, will also be dealt with
separately.
In the year 1883, a “Central Bureau
for the Telegraphic Exchange of Astronomical Information” was established at Kiel. It was arranged
among the principal Observatories that all urgent astronomical
intelligence and discoveries should be communicated to the Central
Bureau at Kiel, which would at once transmit the news to various
secondary centres to be established for the purpose in every part of
the world, and thence to all astronomers concerned. The Melbourne
Observatory was requested to act as the secondary centre for
Australia, and it has since been its duty to communicate to the other
Observatories of Australasia any astronomical news cabled from Kiel,
and to receive announcements of astronomical discoveries or other
important astronomical intelligence from any part of Australasia for
telegraphic transmission to the Central Bureau at Kiel.
Until August, 1884, all meridian observations were made with the
5-inch transit circle, and the results were published in seven
volumes, the first of which contained the work done at Williamstown
as already mentioned. The six subsequent volumes contain all the
separate results from each observation and the annual Catalogues of
concluded Right Ascensions and North Polar distances for each
year.
The first general Catalogue for the Epoch 1860, containing the
positions of 546 stars, is that printed in Volume I. A second general
Catalogue for the Epoch 1870 was prepared and printed in 1874. This
contains the positions of 1,227 stars. A third general Catalogue for
the Epoch 1880, containing 1,211 star places was published in
1889.
In May, 1884, a larger transit circle arrived from England,
constructed by Troughton and Simms, and is of somewhat similar
dimensions and design to those constructed by the same firm for the
Observatories of Cambridge, England, and Harvard College, United
States of America. Its object glass has an aperture of 8 inches and a
focal length of 108 inches. Its two circles are 3 feet in diameter,
being divided to every 5 feet, and each read by four microscopes.
The two circles are at opposite ends of the axis, which is 52
inches in length, and has pivots 4½ inches in diameter. The
pivot bearings rest on two short iron pillars, which stand on massive
stone piers.
The reading microscopes are carried on gun metal circles attached
to the short iron pillars.
From August, 1884, to the present time all meridian observations
have been made almost exclusively with this instrument.
During the period 1884-1891, the astronomical work of the
Observatory was similar in character to that of preceding
years.[pg.343]
The meridian observations made with, the new transit circle
comprised the usual clock stars, a special list of circumpolar stars,
which were assiduously observed year after year, stars employed for
comparison with comets, stars selected by Dr. Auwers for the
formation of a “Fundamental Catalogue
of Southern Stars,” and others in
connexion with the reduction of the Melbourne zones and transit of
Venus observations ; also a list of stars required by the Bureau des
Longitudes for insertion in the Connaissance des Temps, and
another list of stars used by Dr. Gill in some of his heliometer
work.
The observations of the southern nebulae with the great telescope,
and observations made with the smaller equatorials, comprising
extended series of observations of all the comets which were visible
from Melbourne, and a preliminary spectroscopic survey of the
southern stars brighter than the 5th magnitude, form the bulk of the
extrameridional work of this period.
It has been stated in a previous page that the share allotted to
the Melbourne Observatory in the Astrophotographic Programme, which
was agreed upon at the Paris Congress of 1887, covered the south
polar area of the heavens limited by the 65th parallel of south
declination.
Some description of the instrument required for this work has been
already given. The one for this Observatory arrived in Melbourne at
the end of December, 1890.
It was constructed by Sir Howard Grubb, of Dublin, and is similar
in all respects to those constructed by the same makers for the same
purpose for the Observatories of Greenwich and Cape of Good Hope.
It consists of a double telescope, mounted equatorially on a
massive cast-iron stand in what is known as the German model.
The two telescopes are roughly of the same length, but of
different aperture. The larger, which is employed for photographing,
has an object glass of 13 inches aperture and 135½ inches
focal length, and is corrected for spherical and chromatic aberration
for rays close to Fraunhofer’s spectral line G.
The smaller telescope is used for guiding the instrument by visual
observation during exposure. Its object glass is 10.1 inches aperture
and 130 inches focal length. The driving clock is within the stand,
and is controlled electrically by a seconds pendulum, the driving
being corrected automatically by a system of differential wheels
devised by the maker.
In September, 1892, a financial depression necessitated a policy
of retrenchment, and for some years the work of the Observatory was
hampered by the inability of the Government to adequately support it.
The year before the astronomical work of the Observatory had to be
reduced to a minimum Ellery wrote in his report of 2nd September,
1891.
“The work of the year is
clearly before us. The Melbourne portion of the photographic charting
of the heavens, with its collateral work, will use up nearly aIl our
available working power. The meridian work will largely monopolise
the Meridian Observing and Computing Staff, while obtaining
photographs, developing, and otherwise dealing with the plates will
take up the whole attention of two or three members of the staff both
night and day. I propose, therefore, to confine the astronomical
work, for the present at least, to the routine meridian observations,
coupled with the observations for guide stars, and to the special
photographic work with the astrograph, undertaking only such
occasional extra meridian work as may from time to time demand
attention.” [pg.344]
In 1895 the astronomical strength of the Observatory was further
very greatly reduced by the retirement of Ellery in June of that
year. During his tenure of office he had raised the institution from
very humble beginnings to the rank of a “First Order”
Observatory.
We were left, a band of four, to carry out the meridian and the
astrophotographic work. This band remained the same till 31st
December, 1907, after which date a fundamental change took place and
a new epoch commenced for the Melbourne Observatory.
The Annual Catalogues of Stars, observed with the 8-inch transit
circle from August, 1884, to 31st December, 1912, were regularly
constructed and completely prepared for publication, but have not yet
been printed. Those of the years 1884-1893 were used for the
compilation of the Third Melbourne General Catalogue for the epoch
1890 ; the work, which contains 3,100 stars, will very shortly be
ready for issue.
The Annual Catalogues from 1894 to 1912 contain, in addition to
the standard clock and azimuth stars and some 134 zodiacal stars
which were observed at the request of the Cape Observatory, all the
stars which are employed as standard reference stars for the
reduction of the Melbourne plates of the photographic catalogue.
With these annual catalogues, up to the year 1910, a special
catalogue of 6,680 standard reference stars for the epoch 1900, all
observed at least three times, has been prepared.
The total number of stars of this class required for the full
reduction of the Melbourne plates is about 9,160, and 2,480 stars are
therefore still required to complete the Melbourne share of the
astrophotographic catalogue.
Of this number, 636 stars have been observed three times, 379
twice, and 496 once, while 969 stars still remain to be observed
three times. It is estimated that these observations will be
completed by the end of 1914, after which an additional catalogue for
the epoch 1910 will be prepared.
The series of Melbourne catalogue plates has been completed. A
series of chart plates, with single exposures of one hour, covering
singly the whole area around the South Pole down to the 65th parallel
of south declination, has also been completed. In this series the
centres of the plates were set at the even degrees of
declination.
Another series of chart plates, with three exposures of thirty
minutes each, the three images forming a small equilateral triangle
with sides of 8 inches has been advanced to the extent of 431 single
regions out of 584 regions comprised in the full Melbourne area. The
centres of these triple exposure plates were set at the odd degrees
of declination from the 65th parallel to the Pole.
For the measurement of the catalogue plates, an arrangement was
made in 1898, by which both the Sydney and Melbourne plates were to
be measured at the Melbourne Observatory, at the joint expense of the
Governments of New South Wales and Victoria ; a Measuring Bureau was
created and the necessary staff trained at the Melbourne Observatory
for the purpose.
The regular measurements commenced in 1900, but a satisfactory
rate of progress was not reached till 1901.
The computation of plate constants for the Melbourne regions and
the tabulation of rectilinear co-ordinates for publication are now in
course of preparation, and a first volume, containing the zones
−65 and −66, is ready for press. [pg.345]
The total number of stars in this catalogue is over 300,000, and
will occupy eight quarto volumes of about 300 pages each.
On the 1st December, 1908, the Government of the Commonwealth of
Australia took over, and assumed control of, the meteorological
services of the various States uniting them under a single
Commonwealth Department of Meteorology, and thus the Australian
Observatories were freed from a burden which had for a quarter of a
century retarded the advancement of Australian Astronomy.
Since the middle of the year 1908 to the present date, the
principal parts of the working routine programme of the Melbourne
Observatory have still remained the same as those of previous years,
namely, meridian observations and astrophotographic operations.
The meridian observations have been made generally upon the
reference Stars of the Photographic Catalogue, Southern Stars in
Auwers’ Fundamental Catalogue, Stars
selected for investigation of refraction, personal, and magnitude
equation, Clock and Azimuth Stars.
The object of the astrophotographic operations has been to advance
a second series of catalogue plates and the series of chart plates
with triple exposure.
The progress made in the reduction of these observations and in
the preparation of results for publication has already been
stated.
The record of other classes of astronomical observations and
investigations undertaken during the period is as follows :— A
series of 100 photographs and measurements of position of Comet C
(1908) Moorhouse ; thirteen photographs and some 300 comparisons with
stars of Halley’s Comet ; observations
of Comet Borelly (1911e), Gale (1912a), Tuttle (1912&), Faye-Cerully
(1910e), Kiess (19116); observations of Variable Stars of long
period, south of declination -30; investigation of the Reseaux
Melbourne No. 6 and Melbourne N 23 ; investigation of the division
errors of the 8-inch transit circle.
The Adelaide Observatory. In 1855, the late Sir Charles
(then Mr.) Todd was appointed in England Superintendent of Telegraphs
and Astronomical Observer for the Colony of South Australia.
It does not appear that any astronomical work had been done in
South Australia, except for geographical purposes, before Todd’s arrival nor for twelve years after it.
In 1867 the transit instrument of 32-inches aperture and 15 inches
focal length, which had been originally employed at the Williamstown
Observatory, was transferred to Adelaide on loan from the Victorian
Government, and for the purpose of making meridian observations in
connexion with longitude operations required for establishing the
position of the eastern boundary of the Colony. It was not until
1874, however, that a suitable Observatory and some astronomical
equipment were provided by the South Australian Government for its
astronomer. The present Adelaide Observatory was erected in that
year.
The astronomical instruments comprised, at first, an astronomical
clock by Frodsham, the 3½-inches transit instrument borrowed
from the Victorian Government, and an equatorially-mounted telescope
by Cooke and [pg.346] Son, 8-inches aperture, and nearly 10 feet
focal length, provided with all the requisite accessories of a
first-class instrument. The last-named instrument was employed for
the observations of the phenomena of Jupiter’s satellites, for the study of surface
detail of this planet, and for comets.
Meridian observations were made only for determining local time, a
time ball placed on a tower at the Semaphore, 9 miles distant, being
dropped automatically from the Observatory at 1 p.m. daily. The first
time signal was given on 2nd August, 1875.
In 1880 a transit circle by Troughton and Simms, with object glass
6-inch clear aperture, and 85 inches focal length, was obtained,
being similar in design to the transit circle of the Sydney
Observatory, except that the two divided circles at the opposite ends
of the axis are larger, their diameter being 30 inches.
“The first work undertaken was the
observation of stars in Weisse’s
Catalogue, between 0° and 4° south declination, the
intention being to include all stars down to the 10th Magnitude,
between 0° and 15° south, a work which would have occupied
several years. Exclusive of clock and azimuth stars, we had 4,072
observations in R.A., and 4,099 in N.P.D. of stars in the belt
(0−4) referred to, by July, 1892”
(15).
This work was then suspended, Todd’s
attention having been called to the discordance in the observations
of N.P.D. in the South and North Hemisphere.
Observations were made, for latitude, of 297 stars near the zenith
of Adelaide, 118 stars from 1st to 4th magnitude whose zenith
distance ranged up to 30 degrees north and south, observed either
during day or night ; and 127 circumpolar stars so selected that five
or six were observed above and as many below the pole, the same stars
being observed in the reverse order after an interval of six
months.
These were selected from the Greenwich ten-year catalogue
1880.
180 circumpolar stars were observed for latitude in 1894 and 1895,
in addition to a small list of 23 stars, of which several bisections
were made at the same transit and the Nadir taken before and after
every observation, and another list of 53 stars arranged in three
groups —one of stars near the zenith, one of stars about 40
south, and one of stars about 40° north of the zenith. This
latter list was observed at the same time at the Observatories of
Melbourne and Sydney by arrangement.
For some years after 1897 the astronomical work of the Observatory
consisted mainly of meridian observations for time, and occasional
observations of comets and of Jupiter’s
satellites.
The publications of this Observatory have been mainly
meteorological, consisting of annual volumes, dating from 1876 to
1907 inclusive. Various astronomical memoranda, such as observations
of Jupiter’s surface markings,
satellite phenomena, eclipses of the sun and moon, etc., are included
as appendices to these volumes, and some miscellaneous papers have
been printed in the Monthly Notices of the R.A.S. and in
Proceedings of the Australasian Association for the Advancement of
Science. [pg.347]
The unpublished work comprises all the meridian observations made
with the transit circle since the beginning in 1889, and the physical
observations and drawings of Jupiter, of which a large series was
obtained in the years 1884 to 1894, together with a set of over 200
drawings, made during the same period, and arranged for publication
on an orthographic projection.
Sir Charles Todd retired in December, 1906, and was succeeded by
R. F. Griffith, who was appointed Acting Government Meteorologist on
1st January, 1907. He resigned his position at the end of that year
to join the newly-created Department of Meteorology under the
Commonwealth Government, and Mr. G. F. Dodwell, B.A., was then placed
in charge of the Observatory. On 1st June, 1909, Mr. Dodwell was
appointed Government Astronomer of South Australia.
The present programme of astronomical work at the Adelaide
Observatory is as follows : (a) Time determinations ; (b)
Observations of reference stars of Sydney Astrographic Zones ; (c)
Field latitude and longitude determination ; (d) (Seismology)
variables, double stars, and miscellaneous observations with the
8-inch Cooke equatorial.
The observations of variables and double stars have now been
commenced by certain members of the local Astronomical Society, the
equatorial telescope of the Observatory being used for this
purpose.
Negotiations are in progress concerning a proposal to undertake
latitude variation work in conjunction with the La Plata
Observatory.
The instruments of this Observatory at the present day are those
which formed the equipment of the Observatory since 1889, namely, the
6-inch transit circle and the 8-inch equatorial, the additions being
only a portable universal instrument, chronometers and other minor
apparatus.
The Adelaide Observatory is supported by the South Australian
Government and administered as a branch of the State Department of
Education.
The Perth Observatory, Western Australia.
This Observatory started its career in 1896 as an astronomical and
meteorological institution administered as a branch of the Colonial
Secretary’s Department, Mr. W.E. Cooke,
M.A., being appointed Director.
It is situated upon Mt. Eliza — a sand hill some 200 feet
above sea level, rising from the western boundary of and overlooking
the city of Perth — and commands an almost uninterrupted view
of the horizon on all sides (16).
Its geographical position is—Latitude, 31° 57′
10.27″ South ; Longitude, 7h. 43m. 21.74 east.
The climate of the locality is considered very favourable for
astronomical work, except in February and March, and in the winter
months, when observing is more frequently interfered with by smoke,
cloud or rain.
In the first few years of its existence the Observatory was
gradually provided with the following instruments, namely: An 8-inch
reflecting telescope intended for use with a coelostat ; a transit
circle, by Troughton and Simms, with object glass 6-inch aperture and
71 inches focal length, with two divided circles 30 inches in
diameter ; a twin astrographic instrument, by Sir Howard Grubb, of
the standard pattern and size employed by the observatories
co-operating in the international astrophotographic programme ; two
machines for the measurement of astrophotographic plates, similar to
[pg.348] those employed at Greenwich and Oxford; a 12-inch reflecting
telescope; a barrel chronograph, with Grubb’s “mouse” control ; an astronomical clock, by Victor
KuUberg, regulated to sidereal time ; a mean-time clock ; and two
chronometers, a 5-inch theodolite, and minor observatory apparatus,
accessories, and appliances.
For some years the astronomical work of the Perth Observatory was
confined mostly to meridian observations for local time, for the
investigation of instrumental errors of the transit circle and for
the accurate determination of its geographical position. In
the year 1900 the Government of Western Australia was invited to
carry out the astrophotographic programme originally assigned by the
Paris Congress of 1887 to the Observatory of Rio Janerio, which,
however, had not been able to start the work. The invitation was
accepted, and the photographing of the zones comprised between the
parallels of 31 degrees and 41 degrees of south declination was
undertaken by the Perth Observatory. This circumstance established
the nature of the work upon which the transit circle and the
astrograph were to be utilized from that time to the present.
The transit circle was to be devoted to the observation of
reference stars within the Perth photographic zones, and the
astrograph to obtain the requisite photographs of these zones.
This work commenced in 1901. At first, owing to the meteorological
duties of the Observatory, progress was slow, but from the end of
1907, when meteorology became a Federal concern, the work advanced
vigorously, as shown by the extensive publication of its results.
The character of the task undertaken by observatories
participating in the international astrophotographic programme has
been previously described here in connexion with the Sydney
Observatory, and it will be sufficient to remark that the Perth
zones, ranging from −31° to −41°, contain 1,376
regions to be photographed, and that about 10,000 reference stars,
distributed within these zones at the rate of three stars per square
degree, whose positions had to be accurately determined by transit
circle observations, were necessary, according to Mr. Cooke, for the
preparation of his photographic catalogue.
To these two classes of work the Perth Observatory has practically
devoted the whole of its energies and resources, and is still
continuing on the same lines towards the completion of its allotted
share.
The entire area covered by the Perth zones has been photographed,
the whole series containing 1,376 plates, but Cooke found it
desirable to obtain another series, in the taking of which improved
methods were introduced, which gave greater uniformity in the results
; 662 plates of the second series have been obtained and passed as
satisfactory. Three hundred and three plates of the first
series, and 294 plates of the second series, have been measured.
In 1907, Professor Dyson, then Astronomer Royal for Scotland,
offered to assist in the measurement of the Perth plates. His offer
was gratefully accepted. The first plates sent to Edinburgh were
those of zone - 40 degrees. At present some 400 plates have been
measured there and are practically completed (16). [pg.349]
It is stated by the present Acting Director that the series of
plates comprising the Perth section of the photographic catalogue
will be completed, in two or three years. Zone of the plates of the
chart series have as yet been taken.
In the transit circle observations of the reference stars, Cooke
adopted the zone method first introduced by Professor Kustner, of the
Bonn Observatory in the observation of his zone stars.
The observed positions depend on three steps, namely:
1. A fundamental catalogue of a small number of stars.
For the present purpose Auwer’s
Fundamental Catalogue fur Zonenbeobachtungen am Sudhimmel has
been used. This contains, on an average, about three or four stars
per hour between the limits of −31° and −41°
declination.
2. A catalogue of secondary standards, containing
three or four stars per hour for every zone of two degrees between
the above limits. The positions of these stars depend entirely upon
those of the fundamental catalogue, and about ten observations of
each star were taken. This catalogue has been published as the first
volume of Perth observations, under the title of A Catalogue of
420 Standard Stars, etc.
3. The stars of this catalogue form the basis for the
determination of positions of the reference stars, of which four
catalogues were published, in 1908, 1909, 1910, and 1911.
The places of 7,561 stars for the epoch 1900 are contained in
these catalogues.
The plan of advancing all the various phases of the photographic
catalogue as rapidly as possible, by measuring the plates soon after
they have been taken, and regulating the transit circle observations
according to the requirements of the computers for determining plate
constants, and thence the final preparation of manuscript for the
printer, enabled Cooke to commence the publication of his section of
the work in 1911. Vol. I. of the Astrographic Catalogue, 1900, Perth
section −31° to −41°, and three other volumes
bearing the same title, were issued in 1911 and 1912. In these are
registered the rectilinear co-ordinates of 60,481 stars, in the
aggregate, resulting from the measurement of 160 plates, which cover
a belt round the heavens two degrees wide between 31 degrees and 33
degrees of south declination.
The present director estimates that the whole share of the Perth
Observatory in the international astrophotographic work will be fully
published by the end of the year 1918, so far as the catalogue series
is concerned.
The Government Observatory of Brisbane, Queensland.
The Astronomical Observatory at Brisbane may be said to have been
established in the year 1879, when, subsequent to the death of
Captain O’Reilly, a gentleman who had a
private observatory at his home in South Brisbane, the Government of
Queensland purchased his entire outfit, and removed the building to
its present location on Wickham Terrace.
The adopted geographical position is —Latitude, 27°
28′ 00″ south; Longitude, 1Oh. 12m. 6.40s. east.
[pg.350]
The various surveyors-general have successively controlled the
Observatory programme of work. This has primarily been governed by
the requirements of the Survey Department, and was an integral part
of the operations of the trigonometrical survey during its existence.
The taking of observations for time and the supervision of its
distribution per medium of private lines, time ball, etc., is the
only work now performed, and none other is projected under present
conditions.
The astronomical equipment is as follows :
(1) A portable transit instrument, by Troughton and
Simms, of 30 inches focal length, and 2½ inches object glass.
This instrument has been in use for about 30 years.
(2) A sidereal clock, by Cochrane, of Brisbane, with
Eiefler’s pendulum, and seconds contact
for transmitting clock beats electrically.
(3) Combination chronograph and Morse telegraph
instrument, with relay, etc., for recording transits, transmitting
and receiving time signals.
(4) A mean time clock, by Kullberg, of London, with
seconds and hours contacts, also with electro-magnetic attachment for
correcting small errors without touching the clock.
(5) Sidereal and mean time chronometers.
(6) Time-ball apparatus.
For a few years after the establishment of this Observatory the
observations for time were made by the late Sir Augustus C. Gregory,
a versatile and ingenious scientist and famous explorer, who having
then retired from his position of Surveyor-General of Queensland,
took up the work as a hobby and for this purpose constructed with his
own hands a chronograph, relay, and all the apparatus necessary for
electrically recording the observations, including the seconds
contact in the sidereal clock.
Tasmania.
In conjunction with the chief meteorological station of this
State, a Government observatory was established at Hobart on a very
modest scale (reduced indeed to a minimum as an astronomical
institution) for the purpose of determining local time and supplying
the public and the shipping at Hobart with a daily time signal. The
astronomical equipment consisted of a small transit instrument and a
time keeper, neither of these being of high class workmanship.
Owing to complaints made by the Admiralty, in regard to the
occasional uncertainty of the time given by the Hobart Observatory,
the Government of Tasmania arranged with the Victorian Government for
the daily transmission of a time signal at 1 p.m. from the Melbourne
Observatory, which has been used since 1911 for dropping the time
ball at Hobart, and is repeated to other places in that State.
Thus the State of Tasmania is at present without official
astronomy.
Last Update : 18th October 2014
Southern Astronomical Delights ©
(2014)
For any problems with this Website or Document please e-mail me.
|