Letters on Natural Magic, Addressed to Sir Walter Scott

Intended as a supplement to Sir Walter Scott's 1830 Letters on Demonology and Witchcraft, this 1832 publication seeks to explain and expose the science behind the alleged 'magic' of spiritualists and conjurors. David Brewster (1781–1868), a Scottish natural philosopher and historian of science, was highly regarded in his lifetime but has since faded into obscurity. Penned at the request of Scott, Brewster's friend and neighbour, this book follows an epistolary structure, consisting of thirteen letters each addressing and exposing different aspects of the alleged supernatural activity, in keeping with the format of Scott's publication. Brewster's subject matter includes optics, magic lanterns, automata, alchemy, fire-breathing, spontaneous combustion, spectral illusions and various other phenomena. In each case he carefully outlines how this 'magic' is created with optical illusion, narcotic drugs, gas inhalation, and chemical tricks. The book offers an intriguing insight into nineteenth-century attitudes towards the supernatural.

1. Extent and interest of the subject; 2. The eye the most important of our organs; 3. Subject of spectral illusions; 4. Science used as an instrument of imposture; 5. Miscellaneous optical illusions; 6. Natural phenomena marked with the marvellous; 7. Illusions depending on the ear; 8. Musical and harmonic sounds explained; 9. Singular effects in nature depending on sound; 10. Mechanical inventions of the ancients few in number; 11. Mechanical automata of the ancients; 12. Wonders of chemistry; 13. Spontaneous combustion.

Published in 1832 at the request of Sir Walter Scott, this book provides natural explanations for the allegedly supernatural phenomena so popular in the nineteenth century. Brewster, a Scottish natural philosopher and academic, carefully exposes the workings of conjurors by demonstrating the effectiveness of optical illusions and chemical tricks.