Notebook of John Francis Campbell describing the registering sun-dial contrived by him in 1853, with the results of experiments using the appliance recorded for the month of June 1874., 1874, or before, 1879., Adv.MS.50.6.12a. Correspondence and papers, including many manuscripts in Gaelic, journals and yearbooks (with many photographs), albums of watercolour paintings and sketches, and experimental notebooks, of John Francis Campbell of Islay (1821-1885), Gaelic scholar and collector of oral tradition, traveller, scientist, official of the royal household and public servant., Adv.MSS.50.1.1-51.2.7. National Library of Scotland Archives and Manuscripts Division. https://manuscripts.nls.uk/repositories/2/archival_objects/16839 Accessed May 07, 2024.