The fonds consists of a bound manuscript titled "A Series of Letters from Brother to a Sister". It begins with a poem titled "George Marshall to Miss Eliza Marshall, London, August the 22nd, 1777". This is followed by an account of Marshall's voyage on The Charlotte, from England to Bombay, commencing on 20 February [1772?] and ending 21 January [1773?]. The ship sailed from Gravesend and visited Bonavista, St. Jago, Porto Praya Bay, Mayo, Rio de Janeiro, St. Sebastian, Santa Cruz, Tristan de Cunha, Apularia, Cochin, Malabar Coast, Mangulore, Goa and Bombay. There are very full accounts of the towns, customs, birds and animals and other aspects of the settlements visited. There is a map tipped in to face page 11: A View of Porto Praya Bay in the Island of St. Jago. Stamped on the spine in gold is "Voyage to the E. Indies."
Accompanying the manuscript is a letter to Mrs. S. Siwek (presumably a former owner) from A.W.H. Pearsall, Custodian of Manuscripts at the National Maritime Museum, Greenwich, London, dated 22 February 1963. The letter indicates that the Royal Charlotte was an East India Company ship and notes that their records show that the voyage began 1772. The manuscript contains only one date during the voyage, that of 1 January 1772. It is possible that Marshall wrote 1772 when in fact he should have written 1773, as is often the case when the year changes.