This letter was about the list of photographs of Sun taken on different dates and at particular times mentioned.

The fond contain correspondance of M. K. Vainu Bappu with C. V. Raman and mentors, donated by Mrs. Yemuna Bappu to IIA archives.

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

This letter discusses on the predicted formula about the shifts of the solar lines in agreement with the observed values at the red end of the spectrum.

This Letter is from Astronomer Royal to the Director regarding sun photographs for 1911 May 19 and 20

The letter is from Astronomer Royal, Royal Observatory, Greenwich, London, to The Director, Kodaikanal Observatory, Madras, India, requesting to send solar photographs of the mentioned dates as the photographs taken from there are deficient.

This is a letter from Charles. P. Butler, Ag: Director, Kodaikanal & Madras Observatories to Executive Engineer Madura regarding some construction needs at the Solar Physics Observatory, like a permanent building to hold the 4-inch photoheliograph, a glazed verandah for keeping the north-western side of the observatory dry, an open verandah for the Bookbinder's shed and quarters for the writer of the observatory, on which the details will be given later when the decision is finalised.

This letter was about replying to C. M. Smith opinion on uselessness of a table in the solar article for the Monthly Weather Review.

The letter was a reply to Evershed saying that there will be no difficulty in dealing with the 26 inch originals and requesting to provide necessary information.

The letter discusses on the H and K wave-lengths and discusses the recent results that confirm the earlier results, exactly in the case of H and with a difference of 001 with K.