Edward Charlesworth was born on September 5, 1813, in Clapham, Surrey, England.

He was the eldest son of the Rev. John Charlesworth (1782-1864). He studied medicine but abandoned a career in this discipline in 1836 to work in the British Museum as a geologist and paleontologist. He was interested in the Crag fossils of East Anglia and in the period from 1835 to 1838, he debated with Charles Lyell on the age and nature of the Crag formations. At this time, he took over the Magazine of Natural History associated with William Bean. The Magazine of Natural History is, in contemporary scientific literature, often referred to as "Charlesworth's Magazine of Natural History". Charlesworth was the second keeper of the Yorkshire Museum (1844 to 1858). He was also a founding editor of the London Geological Journal, curator of the Museum of the Zoological Society of London (1837-1840), and the Yorkshire Philosophical Society Museum (1844-1858).

He died on July 28, 1893, in Saffron Walden, Essex, England.

Margaret Charlton was born on December 10, 1858 in Laprairie, a small town on the south shore of the St. Lawrence river near Montreal. She was christened Margaret Anne but later changed her second name to Ridley, to honour her descent from the family of the martyred Bishop Nicholas Ridley. Charlton completed a summer course at Amherst College in the newly developed field of librarianship, and is thought to have studied under Melvil Dewey. She began working at the McGill University Medical Library in 1895, shortly after the Library's founding on August 27, 1823. The Medical Library part of the University's Faculty of Medicine and, as was common practice in the nineteenth and early twentieth centuries, a faculty member held the title of "Librarian". Charlton was appointed to be the library's first Assistant Librarian in 1896, likely the first person with any formal library training to work at McGill University. The following year, the British and Canadian medical associations held a joint meeting in Montreal, and it was probably here that Charlton first met Dr. William Osler. William Osler and Margaret Charlton became involved in the formation of the Association of Medical Librarians, founded on May 2, 1898, by four librarians and four physicians who met in the office of the Philadelphia Medical Journal, at the invitation of its editor, George M. Gould, M.D. The object of the Association was the fostering of medical libraries and the maintenance of an exchange of medical literature among its members. Membership was limited to librarians representing medical libraries of at least 500 volumes, with regular library hours and attendance. Charlton served as the Association's first Secretary from 1898-1903 and again from 1909-1911, after it had become (in 1907) the Medical Library Association. She remained at the McGill Medical Library in the position of Assistant Librarian until 1914, when she resigned under less-than-happy circumstances, and moved to Toronto as Librarian of the Academy of Medicine. In 1922 she resigned from the Academy, also under unpleasant circumstances, and returned to Montreal to live with her sisters. She died there on May 1, 1931 and is buried, with her mother and two of her three sisters, in Mount Royal Cemetery.