who came up with the 12 hour clock
12-hour clock The 12-hour clock can be traced back as far as Mesopotamia and Ancient Egypt.[4] Both an Egyptian sundial for daytime use[5] and an Egyptian water clock for night-time use were found in the tomb of Pharaoh Amenhotep I.[6] Dating to c. 1500 BC, these clocks divided their respective times of use into 12 hours each.
Eight-hour day Robert Owen had raised the demand for a ten-hour day in 1810, and instituted it in his socialist enterprise at New Lanark. By 1817 he had formulated the goal of the eight-hour day and coined the slogan: "Eight hours' labour, Eight hours' recreation, Eight hours' rest". Women and children in England were granted the ten-hour day in 1847. French workers won the 12-hour day after the February Revolution of 1848.[3] A shorter working day and improved working conditions were part of the general protests and agitation for Chartist reforms and the early organisation of trade unions.