In 1765, Joseph Priestley published a chart representing the lives of famous men by means of lines arrayed chronologically against a scale of 2950 years. Priestley’s Chart of Biography was not the first timeline. It had a direct precedent in Jacques Barbeu-Dubourg’s 1753 Chronological Chart and earlier roots in chronologies and genealogies, calendars and canon tables, and traditional forms of narrative imagery depicting historical events. Despite the persistence of cyclical gestures, a 1627 chart of the events of the coming apocalypse by Joseph Mede already has something of the modern timeline about it. But none of this made Priestley’s chart any less striking in its day. In fact, the idea of a timeline was still strange enough in the mid-18th century that it required a certain amount of explanation. In his accompanying pamphlet, Priestley argues that although time in itself is an abstraction that may not be “the object of any of our senses, and no image can properly be made of it, yet because it has a relation to quantity, and we can say a greater or less space of time, it admits of a natural and easy representation in our minds by the idea of a measurable space, and particularly that of a LINE.”