This collection was assembled by Court and was partly used in the book, "The History of the Microscope" (with Reginald S. Clay, London, 1932). There is historical correspondence (including some by Court), documents, broadsides, and photographs, concerning microscopes and instruments. This includes material on Joseph Bonomi, James Epps, John Lee, Edward Nairne, and others. There is significant material on Cornelius Varley: account book, autobiographical sketch, watercolors and sketches, etc. This collection also contains a large number of deeds pertaining to the property of John Lee (1783-1866), Fellow of the Royal Society and an amateur astronomer. In addition, there are about 300 pamphlets, including early trade and auction catalogs, used by Court for his research.

This item was written by William Keen for his children and includes genealogy, glimpses of his boyhood in Philadelphia, and reflections on his education at Jefferson Medical College and his medical career. There are accounts of memorable events and surgical cases, including the operation on President Grover Cleveland's jaw. There are mentions of S. Weir Mitchell and other physicians, with historical recollections of such Philadelphia institutions as the College of Physicians.

An Irish-born non-commissioned officer in the 49th Regiment of Foot, Thomas Sullivan served with the British Army in North America from the siege of Boston in 1775 through the last days of the Philadelphia Campaign in 1778. He deserted in June, 1778, and became steward to Continental Army Quartermaster General Nathanael Greene.