who came up with hours minutes and seconds
Hour The seasonal, temporal, or unequal hour was established in the ancient Near East as ​1⁄12 of the night or daytime. Such hours varied by season, latitude, and weather. It was subsequently divided into 60 minutes, each of 60 seconds. Its East Asian equivalent was the shi, which was ​1⁄12 of the apparent solar day; a similar system was eventually developed in Europe which measured its equal or equinoctial hour as ​1⁄24 of such days measured from noon to noon. The minor variations of this unit were eventually smoothed by making it ​1⁄24 of the mean solar day, based on the measure of the sun's transit along the celestial equator rather than along the ecliptic. This was finally abandoned due to the minor slowing caused by the Earth's tidal deceleration by the Moon.
Play clock In all levels of Canadian football, the offensive team must run a play within 20 seconds of the referee whistling the play in; in amateur American football, teams have 25 seconds from the time the ball is declared ready for play. In the NFL, teams have 40 seconds timed from the end of the previous down. Before 2008, in college football, the play clock was 25 seconds after the ball was set, but the clock was not stopped for the ball to be set unless the previous play resulted in a stoppage of the clock. Now, the same intervals as the NFL are used, with minor differences for the final two minutes of each half.[2] Various professional leagues have used their own standards; the XFL, for instance, used a 35-second play clock to encourage faster play.