The seventeenth and eighteenth centuries saw a remarkable florescence in the development of notations in England and France. Dancing masters, doctors, cryptographers, mathematicians, court officials, and even a famous chess player devised the signs and notational techniques that remain crucial to modern disciplines. Yet not only was the sheer number of notational technologies increasing, but also the very idea of just what could be notated began to change. The long-extolled synesthetic property of written language, which was understood to transform the sound, an object for the ear, into a letter, an object for the eye, came to be understood as a potential property of writing in general. Chess, dance, thought, breath, motion—all could be and would be notated. I call the individuals who devised these new notations "technicians of the sign," a title that none of them used. Neither wholly artisans nor wholly scholars, they worked somewhere in between the mechanical arts and the liberal arts of their era, and they drew on artisanal practices as well as scholarly theories to produce new knowledge about notations. By utilizing the numerous manuals that they wrote and the administrative records of their guilds and schools, this dissertation aims to retrace their professional networks and recover the liminal theoretical and practical space in which they worked. Their notations not only changed the way that information could be recorded, I argue, but also enabled new modes of thinking during a period now called the "Scientific Revolution." This dissertation therefore will contribute an important and heretofore unrepresented perspective on the production and circulation of knowledge during the Scientific Revolution by exploring how technicians of the sign challenged what counts as knowledge, how knowledge ought to be represented, and how new knowledge can be produced.