This fond contains official letters, photographs, and administrative files related to P. R. Chidambara Ayer during the years 1919-1932.

The order was on the appointment of Prof. E. B. Ross as Acting Meteorologist, Madras, and Deputy Director of Madras Observatory effective from 1st July 1919. Prof. E. B. Ross was the Professor at Madras Christian College. Meteorological Department issued the order by the Registrar of the Madras Government in 1919.

The letter was to inform Edward Barnes to arrange for trained workers for the magnetic observation that P. R. Chidambara Aiyar was supposed to do.

The item was a letter by P. R. Chidambara Ayer to The Registrar of the University of Madras on submitting an MSc.Thesis. The letter was sent in 1929.

The item is a no-objection certificate issued by C. Karunakara Menon Esqr, Deputy Tahsildar of Kodaikanal, certified that there is no objection to appointing P. R. Chidambara Ayer as Local Bench Magistrate of Kodaikanal.

This fond contains official letters related to William Butler from March to November 1908.

The document is a letter from William Butler, Director General of Stores, to the Director of Kodaikanal and Madras Observatories, Kodaikanal, informing that imperial latern plates required by the Kodaikanal Observatory have been ordered. The product was ordered from Imperial Dry Plate Company, London. The specifications and the quantity of the plates are also mentioned in the letter.

The document is a letter from the Director General of Stores requesting that photographic plates be delivered right away to Kodaikanal Observatory.

The document is a letter from the Director General of Stores to the Director of Kodaikanal and Madras Observatories regarding the poorly maintained photographic plates that were sent to the Kodaikanal Observatory.

The item is a letter from the Director General of Stores to the Director of Kodaikanal and Madras Observatories, enquiring about the sensitivity of the photographic plates supplied to the Kodaikanal and Madras Observatories by the Imperial Dry Plate Company.