Fonds documents A.A. Mackay's medical activities at No. 2 C.C.S. (Casualty Clearing Station) in 1917. The fonds contains two army books of correspondence of Field Service in which case reports are recorded.

The fonds consists of a single 3-page manuscript letter document. Original laid paper watermarked '1805'. Letter is from John MacKellar, dated 16 June 1807. The letter is addressed to the Hon. George Cranfield Berkeley (1753-1818). MacKellar explains his strong reservations about establishing a prison hospital for sick prisoners of war. He warns of high expenses and inconvenience, using the Dartmouth, Nova Scotia, hospital as an example of the expenses required.

Melville Island, in Halifax, Nova Scotia, was formerly known as Kavanagh's Island and used to house French prisoners of war after 1793. The Chesapeake Affair happened six days after this letter was written in 1807 under the command of Admiral G. C. Berkeley.