Agasthyarkoodam, the misty peak and trekkers’ destination on the Western Ghats straddling Tamil Nadu and Kerala, was once home to a forgotten and long-lost 19th-century observatory established by Scottish meteorologist John Allan Broun.
Broun, who used the facility for recording magnetic and meteorological observations in tandem with the Thiruvananthapuram astronomical observatory, was feted by the Royal Society of London for his path-breaking work.
R. Jayakrishnan, Associate Professor of physics at the University of Kerala and the present Honorary Director of the Thiruvananthapuram observatory, has stumbled upon historical evidence about the Agasthiyar observatory from archival records and sketches of the era.
Tracing the origins of the structure perched atop the verdant peak in the annals of history, the researcher pieced together historical evidence to shed light on one of nearly a dozen such observatories that then recorded magnetic observations in the world. His findings have been published in Springer’s Indian Journal of History of Science, peer-reviewed by the Indian National Science Academy.
Broun’s tryst with astronomical observations in India began after he was invited by the ruler of the erstwhile Travancore Uthram Tirunal Marthanda Varma to helm the Thiruvananthapuram (then Trevandrum) observatory following the death of its first director John Caldecott in 1849.
Broun, who was the director of another observatory in Scotland, saw this as an opportunity to expand the network of magnetic observatories developed by the British Association for the Advancement of Science.
A sketch supposedly of Agasthiyar Observatory from Broun’s memoir Report on the Observatories of His Highness the Rajah of Travancore at Trevandrum and on the Agasthiyar Peaks of the Western Ghats.
The meteorologist, who reached Thiruvananthapuram along with his wife and four children on January 11, 1852 took charge of the Trevandrum observatory and set about the task of finding an apt location for another since the research on terrestrial magnetism required simultaneous measurements from two different locations.
Broun, who led arduous treks through treacherous paths to the Western Ghats, zeroed down on the Agasthiyar mountain at a height of 6,200 ft above sea level for his second observatory. His team began to record observations from the observatory in July 1855, two years after they commenced the painstaking labour that involved several hundreds of workers.
A fever caused by inclement weather impaired Broun’s hearing in one ear, prompting him to relocate to Europe in 1859. The observatory remained dormant until his return in 1862. However, difficulty in meeting expenses and other hardships forced its operations to come to a halt in 1865. It was finally closed in 1881 by the then Madras Governor Sir William Denison shortly after the Madras Observatory wound up its magnetic studies.
Broun spent the rest of his life compiling the data collected from the twin observatories of Travancore. He was awarded the Keith Medal from the Royal Society of Edinburgh and the Royal Medal from the Royal Society of London.
Dr. Jayakrishnan says the aftermath of the observatory after its closure has not been documented. The remnants of the structure were also never found.
