The letter was a reply to Turner's letter, that discusses on the spectroheliograph observations

Charles P. Butler sent this letter to Gilbert T. Walker on installing a spectroheliograph in the Kodaikanal Observatory. The letter was sent from the Royal College of Science, London, on 3rd June 1904.

The letter is from the Board of Education, South Kensington, to Charles Michie Smith, informing them about the receipt of 78 spectroheliograms of the sun photographs.

This letter was about the continuation of the delayed telegram of 30th May 1905. It also contains the recommendation of the observatories committee & relating to spectroheliographic work.

This letter was with reference to his Annual Indent for Stores forwarded in the year 1905 and submitting points towards it. The letter also speaks on photographic plates, lower power microscope and spectroheliograph.

This letter was about the work of repairs to the Spectro Heliograph building, Kodaikanal.

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.

The letter is from H. B. Peirce, General Superintendent, Public Works Department, to The Executive Engineer, Madura, explaining the arrangement suggested by Mr. Evershed for moving the sliding roof at Kodai. He said the shaft would pass through the room close up to the wall behind the mirror of the spectroheliograph apparatus, but he also said that he was not satisfied that the arrangement would work well unless a handle and winch were fixed at each end of the shaft.

The letter is from H. B. Peirce, General Superintendent, Public Works Department, to The Executive Engineer, Madura Division, stating the willingness of The Director of Kodaikanal Observatory to have a handle of winch inside; the complicated arrangements proposed formally may be altogether dispensed with, and a cog wheel gearing direct with a pinion may be introduced instead.

The letter is from John Evershed, Director, Kodaikanal and Madras Observatories to The General Superintendent, Public Works Workshops, Madras replying to his letter of 17-09-1907 stating that the distance between the rails of the new sliding roof of that observatory is 14ft. 3 3/4 in. measured from centre to centre of rails.