This letter was about the abstract bill of charges that were incurred for the carriage of "Siderostat" part of the spectroheliograph from Madras to Kodaikanal and request the payment may be made as early possible.

This letter is from R.E.V. Arbuthnot to the secretary to the Government of Madras, Public Works Department, regarding the erection of a building to house the photo spectroheliograph which was being procured from England for the use of the Kodaikanal Solar Physics Observatory.

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

The letter was an enquiry with reference to the Photoheliograph which was received on loan from Greenwich Observatory, whether to return it or it may be completely dismantled and the parts used for other purposes in our research work.

The letter points out that the new wire which was inserted in the Photoheliograph on Nov.14, 1922, does not appear to be taut in its frame. The resulting irregularities make the measure of the Zero point a little uncertain.

The letter was a request for sending copies of all printed forms, instructions, and full particulars of the photographic process in connection with the 8-inch solar photographs done by the Superintendent of Trigonometrical Survey.

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.

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.

The letter was mentioning about enclosed letter from the Director of the Kodaikanal Observatory regarding the disposal of the Photoheliograph on loan from Greenwitch Observatory