This letter was about a drawing of the spectroheliograph that was received at Gilbert T. Walker from the Cambridge Scientific Instrument Company.

This letter was about the spectroheliograph, observations of widened lines in Sunspot spectra and prominence latitudes and frequencies.

This letter was about the indent raised by C. M. Smith, Kodaikanal Solar Observatory that includes Plates for the Spectroheliograph, Ilford Special Rapid, Sandell Special Extra, Imperia Flash Light, Imperipecial Special Rapid.

The letter is from H.B. Peirce, General Superintendent, Public Works Workshops, to The Director, Kodaikanal & Madras Observatories, with reference to the gearing arrangements for moving the roof over the Spectro Heliograph enclosing a plan of arrangements available in shops. He requested to fill the measurement where it is marked 'X' and let know the length of the rack as early as possible.

The letter is from H.B. Peirce, General Superintendent, Public Works Workshops, to the Director of Kodaikanal Observatory, requesting to let know at earliest convenience the exact distance between the rails of the sliding roof of Kodai Observatory lately supplied by the shops.

The letter is from H. B. Peirce, General Superintendent, Public Works Department, to the Director of Kodaikanal Observatory regarding the proposal to have a handle for the roof, enclosing a letter from the Executive Engineer advising to have a second winch on the opposite wall to make the roof move smoothly.

The letter is from H. B. Peirce, General Superintendent, Public Works Department, to The Executive Engineer, Madura Division, forwarding an estimate of Rs. 365 for fitting up rack bar gear to the sliding roof at Kodaikanal Observatory with two winches in the interior.

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 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.

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