Letter to Shackleton to reorder a meniscus lens

This is a letter to Mr Bhaskaran from John Ebvershed about the receipt of the 12-inch lens after figuring out the back surface of the cookie, which was tested and seemed entirely satisfactory.

This letter is from W. G. Butler to the Director General of Observatories enquiring the details of the focal length, etc of a single lens, 4" aperture for Kodaikanal Observatory

A letter from the Director stating the change in focal length of the lens in question is not likely to be found seriously objectionable, if the lens proves satisfactory in other respects

This Letter is from the Director of Kodaikanal and Madras Observatories to the Director General of Stores regrading the details of the lens mentioned in Annual indent

Letter from the Director of Kodaikanal and Madras Observatories to the Director General of Observatories regarding sending the lens details via mail. The specifications of the new lens are enclosed in this letter.

The letter was informing about Dr.Walker has written to the Minister of Finance asking about some spare lenses that they have with a view in borrowing them for use in Kasmir. It informs Evershed the type of lens that could be borrowed till the time.

This letter was reply to letter dated Oct. 29 about lenses. He was requesting 15-inch, 12-inch, 4-inch and a lens of about 7 ft. focus lenses to be send from Nizamaiah Observatory to Kodaikanal Road Station mentioning the purposes for which it requires. In addition the item has the telegram messages written by Evershed to Pocock and vice versa.

This letter contains information about testing of the 15 inch lens on stars etc and finding something wrong in color correction.

This letter is from John Evershed to Mr Bhaskaran about the instructions to pack the 15-inch lens in a large case. He also mentioned that he had put castor oil between the component lenses to keep them perfectly adjusted and saved about 8 percent of light otherwise lost by reflection.