In an age of extraordinary fascination with the senses, Paris at the end of the 19th century witnessed the flourishing of a phenomenon known as "synesthesia", literally "joint feeling." Painters, musicians, poets, playwrights and even perfumers, assumed for their disciplines specific qualities of other artistic spheres with the intention of achieving, for example, a musical painting or music formed with words. The present paper proposes an approach to this fertile framework of sensory correspondence.