This paper examines six exhibitions of machines, clocks, and automata which were performed in the squares, salons and coffee-houses of late eighteenth-century London. It does not take into account those natural philosophers whose enquiries were acknowledged by institutional science, rather focusing on those mechanicks, illusionists, and circus owners (Gulielmo Pittachio, John Joseph Merlin, Benjamin Rackstrow, Henry Breslaw, Philip Astley and James Cox), often collocated in the category of charlatans. By taking into account original advertisements, catalogues and pamphlets, it argues that these shows, with their moments of veiling and unveiling, their dissimilar “methods” to astonish and induce credulity in the beholders, and their separation from institutional venues, were still conceived as places to enlighten and edify the mind, and conveyed concepts such as wonder, deception, curiosity and philosophical understanding to the public.