This letter was reference to letter no.354 of the 3rd instant saying that I regret to find that the labels mentioned para 2 were not enclosed.

This letter was about the list of photographic plates ordered and the serial numbers are not mentioned.

This letter was about the Sandell Ordinary Plates special express and the change in the required plates. Evershed's report on the plates sent by Imperial Plate Company.

This letter was about to send the Sandell plates to test. The second batch of Sandell plates, received by S. S Campbell and it is perfectly evident that isochromatic plates will not stand the journey here.

This letter was about the prints of the spectrum taken on the plates sent by Imperial Dry Plate Company and its relative sensitiveness.

This letter was about the correction regarding the earlier order saying that please include 10 doz. extra in the order for September and 20 doz. extra in the final order (December).

This letter was about the enclosed list of photographic plates sizes and designations.

This letter was about the plates obtained & made up in sealed tins and the instructions for bringing from the maker.

This letter was about sending photographs of the observatory and copies of seismograms.

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.