Letter from unknown person to Tom Harrisson concerning swiftlets Reg Sims had sent to him. The letter also concerned dark birds in the Sarawak Museum; swiftlet skins from Sarawak; bird nests and the likely species of the Kelabit bird

Letter from unknown to the 5th Earl of Cranbrook thanking him for his notes of his interest

Letter from V. Valchera to the 5th Earl of Cranbrook concerning borrowing the Earl's recordings featured in "Birds that Listen in the Dark" shown on 29 Dec 1960. Valchera had been trying to produce an echo sounding device for the blind. Attached: "Sondar: sound direction finding for the blind"

Letter from Vortexion Ltd. to the 5th Earl of Cranbrook informing him that the firm manufactured a Parabolic Reflector to suit the S. T. C. microphone

Letter from W. C. Harvey to the 5th Earl of Cranbrook concerning edible nest trade in Java with photo of swiftlets and nests in a building in Tangerang, West Java attached

Letter from W. C. Harvey to the 5th Earl of Cranbrook on observations of swiftlets occupying houses (upper floors) at Tanggerang and Serang

Letter from Wan Sidik Wan Abdul Rahman to the 5th Earl of Cranbrook informing him the nests were the poor quality type with feathers and were never collected for sale. He also mentioned there were no boats going to Pulau Sembilan islands

Letter to Mr Graham Cowles, Collection Manager, British Museum (Natural History), Sub-Dept. of Ornithology, stating that at the request of Edward Dickinson, they were mailing a package containing 115 collocalia skins. Attached was a list of spcimens

Letter to the the 5th Earl of Cranbrook concerning tabulated data from the observations made from April to June

List of 7 specimens of Collocalia skins sent to Edward C. Dickinson, c/o Graham Cowles, Collection Manager, British Museum (Natural History), Sub-Dept. of Ornithology