Melchisédech Thévenot, a French scientist, invented the instrument some time before February 2, 1661. This date can be established from Thevenot's correspondence with scientist Christiaan Huygens. Within a year of this date the inventor circulated details of his invention to others, including Robert Hooke in London and Vincenzo Viviani in Florence. It is occasionally argued that these bubble levels did not come into widespread use until the beginning of the eighteenth century, the earliest surviving examples being from that time, but Adrien Auzout had recommended that the Académie Royale des Sciences take "levels of the Thevenot type" on its expedition to Madagascar in 1666. It is very likely that these levels were in use in France and elsewhere long before the turn of the century.