The letter was from Charles P. Butler to John Eliot the Meteorological Reporter to the Government of India and Director General of Indian Observatories, Simla, in 1903. The letter is about increasing the power of the apparatus used for sun-spot spectra of Kodaikanal Observatory.

This letter was reply to letter D.O.No.2492 of 26th March 1923 mentioning that nothing very striking to send you in prominences. He sent copy of one of the best plates and 2 disc plates in K light to show rotation.