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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 about photo-visual lens and lens for spectroheliograph for observation in Kashmir

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 is from T. Cooke and Sons Ltd to John Evershed regarding a photo-visual lens. The photo-visual objective must not be correctly connected for spherical aberration. If the lens is returned and the abovementioned issue is there, they will fix it and pay for the carriage both ways.

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.

The letter is from Adam Hilger Ltd to John Evershed, Director of Solar Physics Observatory Kodaikanal. It replies that the three 60° flint prisms are in stock but unfinished. Also, the two-plane parallel glass and the pair of green glass will be sent together to absorb the violet and ultra-violet rays. It also discusses the lack of immediate possibility for finishing the 6" diameter object glass.