John Caldecott

John Caldecott (16 September 1801 – 16 December 1849, Trivandrum) was an East India Company commercial agent, meteorologist and astronomer who worked in the court of the Raja of Travancore at the Trivandrum Observatory.

Caldecott was born in Finsbury in London where his father, also John, and mother Susannah lived. He was christened on 1 November 1801 at St Luke's Church. John Caldecott (junior) went to India in 1820 on the Mulgrave Castle and reached Bombay in May 1821. He worked at Apollo Cotton as an assistant to Daniel West who was a family friend. A relative, William West had an interest in telescopes and microscopes as an evening amusement and this sparked off a scientific interest in John Caldecott. In 1832 he was posted as a commercial agent at the Indian port of Allepey (now Alappuzha) and he saw the need for an astronomical observatory there. This idea was aired in 1836, supported by the Resident Colonel James Stuart Fraser and approved by Raja Swathi Thirunal Rama Varma of Travancore.^[1] An observatory was constructed at Trivandrum. The building was constructed by Captain Horsley of the Madras Engineers. Opened in 1837, Caldecott was appointed as director. Two mural circles, a transit and equatorial telescopes were installed at the observatory. In April 1841, he also brought in instruments to measure the magnetic field of the Earth. He was interested in examining the magnetic field of the Earth at various parts, a scheme inspired by Alexander von Humboldt. He was also very interested in matters of the temperature of the core of the Earth.^[2] He published his observations extensively and pursued these ideas until his death.

Sus mediciones de la temperatura del suelo a diferentes profundidades en Trivandrum le permitieron (y a JD Forbes , quien comentó sus observaciones) señalar errores en las afirmaciones del profesor A. Kupffer , de la Academia Imperial de San Petersburgo, quien dijo que la Tierra es aproximadamente 6 grados más fría que el aire (basándose en mediciones en Rusia) y señaló que Bossingault se equivocó al suponer que la temperatura subterránea por debajo de una profundidad de un pie era constante. ^{[ 3 ]} Hizo observaciones del eclipse solar del 21 de diciembre de 1843 en Parrat, cerca del origen del río Mahé, y notó las perlas de Baily . ^{[ 4 ]} Hizo observaciones de varios cometas. ^{[ 5 ] [ 6 ]} También colaboró ​​con Thomas Glanville Taylor de Madrás y examinó las variaciones del campo magnético en el sur de la India. ^{[ 7 ] [ 8 ]}

Caldecott se casó con Selina, hija de James Somerville Darby de Dublín, el 8 de noviembre de 1825 en Bombay. Sin embargo, este matrimonio no prosperó y ella regresó a Inglaterra en 1827. Se casó de nuevo en 1835 con Sophia Rodgers en Allepey. ^{[ 9 ]} Caldecott fue elegido miembro de la Royal Society y de la Royal Astronomical Society en 1840. Caldecott falleció en 1849 en Trivandrum y su trabajo fue continuado por el reverendo Josiah Sperschneider hasta que John Allan Broun lo sucedió en el observatorio de Trivandrum. ^{[ 10 ]}

• Testamento de John Caldecott
• Biografía de John Caldecott