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Transits of Venus pairs 1761 a&1768 and 1874 & 1882 pplayed an important role in the development of modern astronomy in India under colonial auspices.
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Rajesh Kochhar
President IAU Commission 41: History of Astronomy
Indian Institute of Science Education and Research Mohali 140306, Punjab
Transits of Venus and modern astronomy in India
There is an interesting historical
correlation between astronomical activity
on the one hand and the material status or
aspirations of its practitioners on the
other.
During the past three millennia, in the vast
traditionally interacting geographical area,
the centre of astronomical activity has
resided in the most prosperous,
dominant and ambitious region: Ancient
Iraq, (post-Alexandrian) Hellenistic world,
India, Muslim Culture Zone, Europe, and
USA. (Two major exceptions may be
noted. For some
reason Roman Empire showed no interest
in astronomy. Similarly astronomy failed
to enthuse the Mughal Empire in its peak
period.) It would seem that once a culture
has
established its ascendancy in its terrestrial
surroundings, it considers it its bounden
duty to unravel the mysteries of the
cosmos on behalf of the whole humankind.
The converse is also true.
To compensate for the inherent pettiness of
geo-political rivalries, a cosmic dimension
is added to it. There has been a practical
reason also. There is certain amount of
nobleness
associated with an astronomical pursuit.
This means that more nefarious goals can
be hidden behind it. Thus the 1735 French
expedition to South America was
ostensibly sent for the
measurement of an arc of the meridian at
Quito in Ecuador, but it had secret
instructions to gather intelligence on what
came to be designated the cinchona tree
( Lee 2002 p 191).
Similarly, thirty years later, James Cook’s
expedition to the South Seas for observing
the 1769 Transit of Venus provided Britain
with a pretext to reach New Zealand and
Australia.
It is no more than a coincidence that the
first English ship reached India the same
year (1608) the telescope was invented in
the Netherlands. This numerology
brings home the point that modern science
and technology have grown hand in hand
with colonial expansion, maritime trade,
and domination over
nature and fellow human beings.
Astronomy very soon developed into a
valuable navigational and geographical
aid. The first Astronomer Royal, John
Flamsteed (1646-1719),
supplemented his income by giving tuition
to East India Company cadets. It paid to
join the Company; and it paid to know
astronomy. The 1761 and 1769 transits of
Venus added a strong cultural
dimension to astronomy, made the
Governments aware and supportive of it
and gave a fillip to large-scale manufacture
of instruments.
The 18th century transits occurred at a
time when France and Britain were
engaged in bitter rivalry for the control of
waters and distant lands. The observation
of the transits
became part of this rivalry. For the 1761
event, the Royal Society sent two
astronomers to Bencoolen (now Indonesia)
and asked the British East India Company
to ‘accommodate
and maintain them’. Instructions for the
next event were more forthright. On 22
January 1768, the secretary of the Royal
Society wrote: ‘The honor of this Nation
seems
particularly concerned in not yielding the
palm to their Neighbours, and the Royal
Society intends to exert all its strength and
influence in order to have this observation
[1769 transit] made…’ As it turned out
both the French and the English palms
were left high and dry because of the
cloudy skies over both Madras and
Pondicherry. Astronomical
expeditions and instruments were seen as
symbols of a superior, science-driven
culture. Instruments were presented as
official gifts to native rulers as show-off
even when the latter had no use for them.
A telescope that had earlier been presented
to the Nawab of Arcot was borrowed back
for actual use in 1769.(The Nawab was the
leag owner of land on which Madras
stood.)
The story of the French astronomer
Guillaume Joseph Hyacinthe Jean-Baptiste
le Gentil (1725-1792) is well known. He
has the rather tragic distinction of holding
the record
for the longest scientific expedition in the
recorded world history, and that too an
unproductive one.. He set sail for South
India with a view to observing the 6 June
1761
transit of Venus; and stayed back for
1769. He reached back home after 11
years, and that too without accomplishing
his mission. Because of the Anglo-French
war, he could not arrive in India in time,
and
could observe the event only from a
moving ship, which observation obviously
had no scientific value. He decided to stay
put in the East for eight years to be able to
see the 3 June 1769 transit from
Pondicherry , but was clouded out (Hogg
1951, p. 129). His time however was not
entirely wasted.
Gentil arrived in Pondicherry in March
1768 and stayed here for two years, before
and after the transit. He took tuition from
Tamil astronomers and learnt the
traditional Indian method of calculating
eclipses (Hogg 1951, p. 129).
When Greenwich Observatory was
established, it had no instruments. British
India now had instruments, but no
Observatory. However, what led to the
institutionalization
of modern astronomy in India was not the
love of the stars but the fear of death. The
Bay of Bengal is visited by monsoons
twice a year. The east coast of India,
the Coromandel, is rocky and full of
shoals. On top of it, Madras, unlike
Bombay, is not a natural harbour. A survey
of the coast was thus literally a matter of
life and death.
It is to facilitate coastal survey that an
astronomical Observatory was established
in Madras, in 1787. It was a private
Observatory to begin with but was taken
over by the Government in 1790.
One of the instruments was a clock by
John Shelton, which had been made for the
Transit. It is identical with the clock used
by Captain James Cook, and in the
determination of Mason-Dixon line in
USA.
It is not clear when the East India
Company bought the clock and sent to
India. It is now at Kodaikanal and still
accurate enough to be used as an ordinary
timekeeper.
In 1844, after ten years of sustained work,
Thomas Glanville Taylor at Madras
Observatory brought out the famous
Madras Catalogue of more than 10,000
stars, which won high appreciation.
It was however the only worthwhile
contribution from Madras, which lost its
charm for the British after the
establishment of Observatories in South
Africa and Australia.
Madras Observatory had been established
as an aid to Trigonometrical Survey of
India. Once the Survey became self-
sufficient, the Government lost interest in
the Madras Observatory.
The attitude towards pure astronomy is
best brought out by a little -known
incident. In 1834, on orders from the
Government, instruments were issued to
John Cumin for
the observation of the opposition of Mars.
The Surveyor General, George Everest,
made a strong protest against the loan,
sayings: ‘The discoveries which the late
astronomer
of Bombay is likely to make in science
would hardly repay the inconvenience
occasioned by retarding the operations of
the Great Trigonometrical Survey...’
Curnin had been the first Director of the
Colaba Observatory and was dismissed
from service in 1828. His stock would not
have been very high in British India.
And yet, the incident does sum up the
lowly position which pure astronomy
occupied in relation to geodesy and
geography.
By the time the 1874 transit of Venus
came, positional astronomy had made way
for physical astronomy. Spectroscopic and
photographic techniques were used in the
Indian observations of the solar eclipses of
1868, 1871 and 1872, which attracted
observers from Europe also. The French
astrophysicist Pierre Jules Cesar Janssen
independent co-discoverer Joseph Norman
Lockyer (1836-1920). During his post-
eclipse stay at Simla, Janssen created the
first spectrohelioscope, which facilitated
daily examination of the sun.
independent co-discoverer Joseph Norman
Lockyer (1836- 1920). During his post-
eclipse stay at Simla, Janssen created the
first spectrohelioscope, which facilitated
daily examination of the sun.
The scientists’ agenda for the 1874 transit
ran deeper. What was advertised was the
momentary passage of Venus in front of
the solar disc; what was planned was a
long-term
study of the disc itself. British (and
European) solar physicists wanted
photograph of the sun for each day of the
year. Since this was impossible in
Europe’s weather conditions,
data was needed from the colonies. The
British Association for the Advancement
of Science even passed a resolution asking
the Government of India to make
arrangements
for observing the event and to provide
instruments which were afterwards to be
transferred to a solar observatory. Such
was the prestige enjoyed by science and
scientists
in Europe at the time that the British
Empire as the owner of most of the
world’s sunshine could not but respond
favourably even if partially.
The 1874 transit eventually led to regular
solar physics studies in India, even though
the exercise took 25 years. The stepwise
development was as follows.
Telescopes were purchased expressly
for the observation of the 1874 event
Facilities of a more permanent nature
were then created using these and
other telescopes. Solar photography
was taken up at Dehra Dun (1878-
1925) and solar spectroscopy Poona
(1888-1912). Data was sent to Britain.
A Solar Physics Observatory was
established at Kodaikanal in 1899
which now has solar picture data with
the same instrument for the longest
uninterrupted period.
The 1874 transit of Venus
As part of a bigger programme, and
under the guidance of the Astronomer
Royal, Sir George Airy, the transit
observations were planned at Roorkee
( now Uttarakhand) and Lahore, under
the supervision of Col. James Francis
Tennant. Note that it was Tennant and
not Airy's bete noire, Norman Robert
Pogson, the Madras Astronomer, who
was asked to do this work.
More than 100 photos of the sun were
taken at Roorkee and sent to Airy.
Photos from all over were reduced by
Captain G. L. Tupman who wrote:
‘There is only one really sharp
image in the whole collection, including
the Indian and Australian contingents,
and that is one of Captain
Waterhouse’s wet plates taken at
Roorkee’.
Dehra Dun Observatory (1878-1925)
Next, Lockyer used his equation with Lord
Salisbury, the Secretary of State for
India, for making arrangement for
solar photography in India.
Salisbury wrote to the Viceroy on 28
September 1877: ‘Having considered
the suggestions made by Mr. Lockyer,
and viewing that a study of the
conditions of the
sun’s disc in relation to terrestrial
phenomenon has become an important
part of physical investigation, I have
thought it desirable to assent to the
employment for a
limited period of a person qualified to
obtain photographs of the sun’s disc by
the aid of the instrument now in India [
for the transit]’. Accordingly, starting
from early 1878 solar
photographs were regularly taken at Dehra
Dun under the auspices of Survey of
India, and sent to England every week.
Dehra Dun continued solar
photography till 1925, but
more out of a sense of duty than
enthusiasm. The larger of the two
photoheliographs fell into disuse, and
in 1898 Lockyer was stung by on-the-
spot discovery that ‘the dome has been
taken possession of by bees’.
St Xavier’s College Observatory, Calcutta
(1879)
sunny India caught the attention of
astronomers in the continent also. The
Italian transit-of-Venus team led by
Professor P. Tacchini
of Palermo Observatory stationed itself in
Bengal, its Chief instrument being the
spectroscope, `an instrument not
recognized in the equipment of any of
the English parties’.
A co-opted member of the Italian team was
the Belgian Jesuit Father Eugene Lafont
(1837-1908) professor of science at St.
Xavier’s College, who though no
researcher himself was an inspiring educator
and science communicator. Tacchini
suggested to Lafont ‘the advisability of
erecting a Solar Observatory in Calcutta,
in
order to supplement the Observations made
in Europe, by filling up the gaps caused
in the series of solar records by bad
weather’. St Xavier’s was an elitist
College providing
education to sons of Europeans, Anglo-
Indians, rajas, zamindars, and Indian
men of note. Lafont therefore `secured
great influence among these classes’
which he now put to good use in the
service of science.
Lafont soon collected a sum of Rs 21000
through donations, including Rs 7000
from the Lieutenant Governor of Bengal.
A 9” refractor by Steinhill of Munich
was
purchased and housed in a spacious dome
constructed for the purpose.
Unfortunately, no research or teaching
use was ever made of
this facility. This is unfortunate, because
observational astronomy has remained
outside the education system.
Takhtasinghji's Observatory Poona (1888-
1912)
Set up by the Bombay Government, it was
India’s first modern astrophysical
observatory. Unfortunately, it was a
personalized facility. The original plan was
to establish a spectroscopic laboratory at
Elphinstone College Bombay for use by
the students. The initiator of the proposal
was a
lecturer in the College, Kavasji Dadabhai
Naegamvala (1857-1938), who obtained
seed money of Rs 5000 from the
Maharaja of Bhavnagar and a matching
grant from the Bombay Government.
While in England in 1884 for buying the
equipment, he was persuaded by the
Astronomer Royal and Lockyer to build
a spectroscopic observatory instead.
Since Poona was a better astronomical site
than Bombay, in 1885 Naegamvala was
transferred there to College of Science
where the Observatory came up in 1888.
Since Poona was a better astronomical site
than Bombay, in 1885 Naegamvala was
transferred there to College of Science
where the Observatory came up in 1888.
Its chief instrument was a 16½ inch aperture
silver-on-parabolic glass Newtonian
made by Grubb. In addition, Lockyer
equipped Poona as a satellite facility.
A six-inch Cooke equatorial purchased by
the Government for the 1874 transit
observation from India had been loaned
to Lockyer’s Observatory in South
Kensington.
The India office also purchased two
spectroscopes from Hilger (one solar, the
other stellar) for his use. The equatorial
and the spectroscopes were given to
Naegamvala so that he could observe
with them and send raw data to Lockyer
From December 1903 to November 1904 in
Poona, observations were made on as
many as 327 days. Out of these, 31 days
were unfavourable for any observations,
and on six
days no spots were recorded. Spectroscopic
observations were made on 216 days,
and 422 sunspots examined. Dehra Dun
sent a total of 488 8-inch negatives
during 23 October 1903 to 6 November
1904. Similarly data was received from
Kodaikanal and Maurtius.
Expectedly, relationship between Poona and
South Kensington was uneven.
Whenever South Kensington found fault
with data collection at Poona, it did not
write directly,
but formally complained to Naegamvala’s
British superiors. Yet, when Kodaikanal
Observatory was being planned, Lockyer
suggested Naegamvala’s name for the
directorship.
but formally complained to Naegamvala’s
British superiors. Yet, when Kodaikanal
Observatory was being planned, Lockyer
suggested Naegamvala’s name for the
directorship.
The position was however offered to an
Englishman, Charles Michie Smith, a
non-descript physics professor at
Madras. Lockyer and Astronomer Royal
constituted two independent centres of power
in England, and Kodaikanal came under
the latter’s sphere of influence.
Naegamvala took observations till the very
last date of his employment, 11 January
1912, ‘when in accordance with the
official notification,
the existence of the Observatory was
terminated’, and all equipment was sent
to Kodaikanal.
Thus instead of creating a permanent
educational facility, a temporary research
facility was created for the primary
benefit of European solar physicists.
Kodaikanal Observatory (1899)
If the 1874 transit of Venus was important
for solar physicists, so was the severe
famine of 1876-77 in the Madras
Presidency. Monsoons fail at times, but
the severity of famines was
particularly high in the colnial period
because of large-scale export of food
grains from India to Britain in utter
disregard of local requirements. This of
course is a later
assessment. In 1879, Lockyer presented a
report to the Indian Famine Commission
claiming that famines were correlated
with sunspot minima.
There is no doubt that Lockyer and many
others genuinely believed in a correlation
with solar activity and terrestrial
weather.
But is also a fact that the practical benefits to
be derived from a study of the sun were
exaggerated to gain Government support.
In 1881, Government of India’s chief
meteorologist Henry Francis Blanford
reported to the Famine commission that
no such simple correlation as suggested
by Lockyer existed.
In any case, the Government decided to go
ahead with the Solar Observatory. It was
decided to wait till the neurotic Madras
Astronomer Pogson was dead. This
happened in 1890.
Steps to set up Solar Physics Observatory
were initiated in 1893, culminating in the
Kodaikanal facult which formally came
into existence on 1 April 1899.
Kodaikanal started shakily, but rose to great
heights under George Evershed who
arrived in 1907 no doubt to be able to
work in solitary splendour.
His 1909 discovery of the Evershed Effect
of radial flow in sunspots remains the
most outstanding work ever done in the
Observatory.
Concluding remarks
In the 18th century, when Britain and France
were fighting for control of maritime
trade and distant lands, astronomy
became a symbol of one-up-manship
( cf. space race between USA and
USSR in the cold war era).
By the time of the 19th century transits of
Venus, Britain had become the
uncontested world power. Science had
sufficiently progressed in the West to
give the scientists a high social and
political profile.
Supporting pure science was a proof of the
good sense of a Government. ( In the
18th century, support for geodesy,
geography and natural history by
the Dutch and English East India Companies
pleased the scientific community and
diverted attention away from the
Company’s unsavoury activities.)
A large number of telescopes were made for
purchase by the British Government for
field expeditions. These later became the
nucleus for observatories.
It was fortunate that before and after the
1874/1882 transits a number of solar
eclipses took place in quick succession.
There was thus created a climate
supportive of pure astronomy.
Indian experience provides a number of
valuable lessons which are relevant
even today for all.
The most outstanding contributions
from Madras and Kodaikanla
Observatories were the Madras
catalogue of southern stars (1844) and
Evershed Effect (1909). These were
also the only times when India had
state-of -art instruments.
•Up to the first half of the 20th century,
the technological base of pure science
was quite modest. India could maintain
the equipment it had and improvise
also. But with passage of time science
has become
more and more a child of high technology to
the extent that in industrially-
challenged countries, (imported)
equipment tends to overwhelm the user
rather than be a tool in their hand.