Letter from the 5th Earl of Cranbrook to Ben King commenting on John Darnell's notes. The Earl also commented on swiftlets found in Singapore, Malaya and Borneo

Letter from the 5th Earl of Cranbrook to Betsy Garrett Bang commenting on the relatively large areas of olfactory mucosa in esculenta

Letter from the 5th Earl of Cranbrook to Betsy Garrett Bang informing her he was sending her fixed heads of certain species of swiftlets

Letter from the 5th Earl of Cranbrook to Birdlife International requesting for funding for Malaysian delegation to attend BirdLife International World Conference in Kuala Lumpur. Attached: "An invitation to the Birdlife International World Conference : Kuala Lumpur, Malaysia 13-17 October 1999 : hosted by the Malaysian Nature Society Birdlife Partner in Malaysia"

Letter from the 5th Earl of Cranbrook to C. H. Jolly informing him two members of his department (Mr Orville Elliot and Mr Ben Ensoll) would be available at 48 hours notice to go to Pulau Sembilan islands when there was a boat going there on official business.

Letter from the 5th Earl of Cranbrook to Chris Hails concerning Hails' paper "The Feeding Ecology of the White-Bellied Swiftlet (Collocalia esculenta) in Peninsular Malaysia". Paper attached with letter

Letter from the 5th Earl of Cranbrook to Clifford B. Firth of Phuket Marine Biological Center enclosing Table 2 giving details of the eight habitats Firth worked on Aldabra. The Earl also mentioned he would do the detailed editing of Firth's work in the latter part of 1975.

Letter from the 5th Earl of Cranbrook to Datuk Leo Chai, Director of Forests, Sarawak concerning progress report on conservation and sustainable management of cave swiftlets

Letter from the 5th Earl of Cranbrook to David Labang concerning the Earl not being to go to Sarawak in August, but he could go in October

Letter from the 5th Earl of Cranbrook to David Labang concerning the Earl's intention of writing a book on swiftlets. The letter also mentioned a proposed report with provisional title "Cave swiftlets : the birds'-nest soup birds of Southeast Asia"