SINCLAIR, George. Satan’s Invisible World discovered: or, a Choice collection of modern relations, proving … that there are devils, spirits, witches, and apparitions … To which is added, that marvellous history of Major Weir and his sister, etc.



Edinburgh: William Martin, 1789.








Sixth edition. 8° (10 x 16.5 cm), [ii], pp. 174, [ii].  Title page, table of contents, 42 chapters. Initial flyleaf with small tear. Insignificant wormhole on upper margin of title. Slight foxing and browning throughout, not affecting text. Contemporary calf, slightly darkened. Spine in compartments with raised bands; gilt label. Date at foot of the spine. Ex-libris of Sir James Buller East, 2nd Baronet on front pastedown. A fine copy.



George Sinclair (d. 1696) was the first Professor of Mathematics at the University of Edinburgh, an engineer and demonologist. In 1666 he was removed from his post at the University for being a Presbyterian and thus started working as a surveyor and engineer, particularly for Sir James Hope. He was eventually reappointed Professor of Mathematics in 1691.


An author of many books on different subjects, Sinclair’s most famous book is undoubtedly Satan’s Invisible World Discovered, first published in 1685. In this work Sinclair describes the poltergeist incident of the Devil of Glenluce, which was alleged to have terrified the household of the weaver Gilbert Campbell between 1654 to 1655. Alexander Agnew, a beggar who was refused a handout by Campbell, promised to cause the family harm and since then strange phenomena started happening in the house. These included demonic voices, strange whistling sounds, stones being thrown, and warp thread being cut. Sinclair described the incidents as having a usefulness for refuting atheism, as evidenced by the title page of the book itself.


Sinclair’s source for this story was Thomas, a philosophy student at Glasgow University and  son of Gilbert Campbell. It was later suggested that it was Thomas who had produced the supernatural phenomena through fraudulent means.


Satan’s Invisible World Discovered was very well received and was extremely popular, especially in Scotland, with editions of the full text published in Edinburgh in 1709, 1746, 1769, 1779, 1780, 1789 and 1808, and in London in 1814, as well as an abbreviated chapbook selection from Stirling in 1807 and at least three Glasgow chapbooks between 1830 and 1840.



Bibliography: This edition not in Ferguson; Sinclair, George (d.1696) in Dictionary of National Biography. London: Smith, Elder & Co. 1885–1900; Barry J., News from the Invisible World: The Publishing History of Tales of the Supernatural c.1660–1832. In: Barry J, Davies O, Usborne C, editors. Cultures of Witchcraft in Europe from the Middle Ages to the Present. Cham (CH): Palgrave Macmillan; 2017. Available from: doi: 10.1007/978-3-319-63784-6_9