The letter is from M. K. Vainu Bappu, Nizamiah Obsevatory to Prof. Raman telling that it is best to plan on acquiring equipment specifically for research on the sun. Adding that the sun plays important role in our general understanding of Astrophysics.

This letter was discussing on financial resource, disposal and acquiring equipment specifically for research on the Sun. Further he mentioned about solar telescope and high dispersion spectrograph, tower telescopes at Mt.Wilson, Potsdam Arcetri and trend of problems in solar research.

The letter from Harlow Shapley to Prof. M. K. Bappu telling that he will pass the kind note of indebtedness of him and his son to Mr. Campbell. It also say about his son's honor of geting special fellowship at the Mount Wilson Observatory

This letter was a reply note of June 29 of M. K. Bappu father of M.K.Vainu Bappu about the indebtedness of both to Mr.Campbell. Further, Harlow Shapley mentioned his enjoyment with M.K.Bappu and his wife with their son in America. Shapley mentioned that probably you have heard that if your son had not gone to Mount Wilson we would have offered him a half-year lectureship in the Harvard University.

This letter was about the Bappu's application for admission into Harvard Observatory and the formalities discussed by Harlow Shapley.

This letter was about the M. K. Vainu Bappu's application to National Institute of Science of India. A testimonial from Shapley on Bappu's professional knowledge in observational, analytical astronomy and astrophysics and his work in observatories.

This letter was to inform C. V. Raman was thankful for the letter of the 4th April, 1954, which he read with much interest.

This letter was asking question on using telescope mirrors made of cast aluminium or other light metal, which could be cheap and easy to make and also what kind and size of grating, its makers and price to building a solar observatory.

This letter was to inform on M. K. Vainu Bappu's research on Sun. It also mentioned finding a location for the Solar Physics Observatory and also asking Bappu for the present address of Zeiss and of Cox, Hargreaves and Thomson.

The letter is from C. V. Ramam, Raman Research Institute to M. K. Vainu Bappu, Nizamiah Observatory asking about using telescope mirrors made of cast aluminium and about diffraction grating as a preliminary to building solar observatory.