Showing 5 results

The fond contains correspondence between E. C. J. Bond, the officer-in-charge, No. 18 party (Magnetic), Survey of India, and the Director of the Kodaikanal and Madras Observatories during 1919-1920. The official letters are about the magnetic observations from the Kodaikanal Magnetic Observatory. The observations have been taken from the Kodaikanal Observatory and used to send to The Survey of India office for scientific purposes. This fond consists of 7 letters sufficient to understand the cooperation between The Survey of India and The Kodaikanal Observatory.

This item was a magnetic compass which was used by M.K.Vainu Bappu during the visit to Kavalur for site survey. The magnetic compass is a tool used for determining direction on the surface of the Earth. It operates by using a magnetic pointer that aligns itself with the Earth's magnetic field. This type of compass is the oldest and most commonly used in various forms of transportation such as aircraft, ships, and land vehicles. The Earth's magnetic field acts as an enormous bar magnet with a North-South field that causes freely moving magnets to take on the same orientation. Although the direction of the Earth's magnetic field is not entirely parallel to the North-South axis of the globe, it is close enough to make an uncorrected compass a reasonably good guide. The inaccuracy, known as variation (or declination), varies in magnitude from point to point on Earth.

The album includes documents on the results of astronomical observations and photographs related to the Madras Observatory. A copy of the first observation made at the Madras Observatory and a page from Madras M. S. record is preserved with photos of the Madras Observatory, Shelton clock and granite slab with Latin inscription at Madras Observatory. A map of Madras Observatory land in 1826 and a sketch of John Goldingham swinging Kater's pendulum hung in front of Haswell clock in the observatory.

The album contains archival documents related to the building, instruments and observations at the Madras Observatory. It mainly includes an old photo of the Madras Observatory, a photocopy of the first observation taken in 1786 from the observatory, two pictures of Kater's pendulum hung in front of the Haswell clock in the observatory, a sketch of the Madras Observatory building from 1848 Taylor's catalogue and painting of Madras coast by Daniel.

The book Traite experimental of de L'electricite et du Magnetisme transalates to Experimental Treatise of Electricity. M.Becquerel, of the Academy of Sciences of the Institute of France, wrote this book. It is published in 1840