Did you know?
Some eighteenth-century watch mechanisms feature an à toc or à tact repeater (sometimes both). The à toc repeater, invented by Julien Le Roy, uses a tiny hammer to indicate the time by striking not a gong but the case. In the à tact repeater, a sharp pin protrudes from the case and pricks the finger or skin once for each hour. Already in use in the sixteenth century, most famously in a ring watch belonging to Elizabeth I, these mechanisms were revived by watchmakers of the Enlightenment, when it was considered impolite to look at one’s watch in company. The French expression “avoir du tact”, meaning to be tactful, originates in this type of watch.