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 letter is about water vapour observations. Bappu was also asking whether the point source lamp was used. He also mentioned that he would be in Bangalore on April 27.

This letter was about spectroheliograms that Saxenas sent to him. He suggested to improve on this by another factor of 200%. He explains his idea to work on spectroheliogram.

This letter was explaining the Saxena's present programme of going to Lucknow.

This letter was to replying Dr.M. K. Vainu Bappu for telling the improvements required in the spectra for H & K emission.

The CD contains photos of the ceremony of J. C Bhattacharya's 1.3 meter telescope. It also contains photos of various eminent persons' speeches etc.

This letter was about water vapour measurement made at Kodaikanal.

This letter seeking a clear spell of an hour in the Sagittarius region and a spectrum of Upsilon Sagittari.

This letter was about the BARC image convention and the M. K. Vainu Bappu's visit.

The fond contain compilition of Newspaper clipping, photographs and graphs of Uranus ring observed at Kavalur observatory