The majority of the collection is made up of journals kept by Buckle during the years 1866-1870, during which he travelled to South America, South Africa and Australia (there are also periods during which he was stationed at Portsmouth). There are some lacunae in the sequence of diaries. There is also one autograph album kept by Buckle relating partly to his own affairs (his application to become House Surgeon at the West Norfolk and Lynn Hospital, 1863-1864) but also including older material predating his birth.

Collection comprises correspondence with Philip Hammersley Leathes, manuscript papers, diaries, devotionals, dictionaries and pedigree rolls, title deeds and indentures, printed books and pamphlets, catalogues and the manuscripts of the architect, John Carter, [1350-1863]. Notably including correspondence from George Nayler of the College of Arms and Nicholas Carlisle, Secretary of the Society of Antiquaries, relating to publications of the Society, discoveries of antique brass plate, and the exchange of manuscripts between antiquaries, [1790-1838]; loose manuscript papers collected by Leathes, describing ornamentation in early printed devotionals, a fictional narrative entitled 'The amorous Jill: A tale', narrative of the Lisbon earthquake of 1755, notes relating to the observation of comets, including the comet of 1811, copies of charters of the reigns of Edward IV and Henry VII, papers relating to the Portland Vase, British Museum, fragments describing inscription on newly discovered brass plate, 1747-1829; pedigree rolls tracing the lineage of the English Crown, [1450, 1762]; manuscript volumes including collection of biblical extracts, liturgical handbook, autograph book with colour illustrations, antiquarian ephemera such as funeral memorials, armorials and the creation of nobles, volume by Francis Harrison entitled, 'The elements of navigation' with colour charts, tables and illustrations, dictionaries of Celtic and Saxon words, notes on the teaching of mathematics, commonplace book drawing on ancient and modern authors, manuscript diary including progress of architectural tour of Europe; title deeds and indentures for families in Nottingham, Southampton, London and Hungerford, residency certificates in Buckinghamshire and Northamptonshire, 1650-1751; printed books and pamphlets on the subjects of antiquarianism, genealogy and architecture, 1778-1853; manuscripts of John Carter, architect, acquired at his death in 1817 by his executor, Leathes, notably including autobiographical notebooks by Carter describing architectural subjects and tours, commonplace book, correspondence with Leathes, loose notes on linguistics and the ships of the Russia Company, obituaries of Carter and sale catalogue from his estate, 1700-1818; manuscript catalogues and display captions relating to the Leathes' papers, King's College London, 1819, 1837.

Papers and correspondence, 1846-1974, of David Meredith Seares Watson and his family, largely comprising biographical material and family papers, scientific correspondence, and photographs, also including a few Exchequer receipts, 1568-1622.

Biographical material, 1886-1974, includes Watson's birth certificate, 1886; documentation, including certificates and correspondence, of Watson's career, honours and awards over a period of forty years, including election to the Fellowship of the Royal Society, 1922, the award of its Darwin medal, 1942, and the Wollaston Medal of the Geological Society, 1965; correspondence about the Directorship of the British Museum (Natural History), 1937; correspondence about the presentation album on his retirement from the Jodrell Chair, 1951; correspondence and papers relating to his final retirement from research, 1965; obituaries, 1973; F R Parrington and T S Westoll's memoir of Watson from Biographical Memoirs of Fellows of the Royal Society, 1974; an account of Watson's early days and family background by his daughter Janet Vida; recollections by his research assistant Joyce Townsend; Watson's curriculum vita and bibliography.

Family papers include the birth certificate of Watson's father, David, 1846, correspondence with his wife Mary, 1888, and a letter of condolence to Mrs Watson on her husband's death, 1899; diaries of Mary Watson, 1881, 1885; birth certificate of their daughter Constance, 1888, letters from Constance to her brother David Meredith Seares Watson, 1905-1909 and undated; papers relating to Katharine Margarite Watson (née Parker), Watson's wife, including her birth certificate, 1891, marriage certificate, 1917, death certificate, 1969, and various correspondence; papers relating to Watson's daughter Katharine Mary, including letters of congratulation on her birth, 1918, and letters to her parents, 1950, 1955; material relating to Watson's mother's family, including letters of her father Samuel M Seares, 1871, 1879-1882; papers of Charles J B Hutchinson, 1879-1880, who emigrated to Australia after his engagement to Watson's mother was broken off but who remained in correspondence with her aunt, Fanny Rossiter; other Parker family papers, 1929-1972; miscellaneous other personal correspondence, 1896-1965.

Four Exchequer receipts dated 1568, 1580, 1616 and 1622 were found enclosed with a letter to Watson's wife.

Scientific correspondence of Watson, sometimes including photographs of fossil specimens, with leading palaeontologists in Africa, 1947-1953, America, 1915-1964, Australia, 1931-1962, China, 1926-1927, 1935-1964, England, 1913-1914, 1920, 1926-1960, France, 1930-1936, 1945-1956, Germany, Austria, Hungary and Czechoslovakia, 1920-1962, Russia, 1920-1962, and Scandinavia, 1922-1964, and with the palaeontologist Robert Broom, 1911-1950, and Watson's research assistant Joyce Townshend, 1929-1973, also including a few letters from Watson's wife and scientific colleagues, and an obituary of Watson, 1974; correspondence and papers on bones found at Qau, Egypt, 1930-1957, 1972; miscellaneous other palaeontological correspondence, 1912-1967. There are few copies of Watson's outgoing letters before the end of the Second World War.

Photographic material comprises photographs documenting Watson's career, [1912]-1965 and undated, some including colleagues; photographs of scientific colleagues, 1911-1951 and undated, including Watson's predecessor as Professor at University College London, J P Hill, and Robert Broom; album of photographs and signatures presented to Watson, 1951; undated family photographs, including a photograph of Watson as a boy, photographs of members of the Seares and Parker families, and photographs of Watson's wife, Katharine Margarite, and daughter, Katharine Mary; photographs of unidentified fossil specimens.

Royal Society Darwin Medal Award given to Watson, 1942.