|Around the Academy:
As the title suggests, the umpire tapping his wristwatch would signal that the last hour of play has commenced.
In Test matches, we have a minimum number of overs to be bowled in a day and 15 must be bowled per hour.
The last hour starts at 5pm, unless there are circumstances where an hour or more of play has been lost and we can make up to an hour's play back that night.
Some international boards agree that you may add the time on at the start of the following morning.
In England, because we have lighter evenings, we tend to add the time on at the end of the day.
At Test venues abroad, where the sun goes down very quickly, they may split the hour between the beginning and the end of the day's play.
On the last day of a county game, when 96 overs have to be bowled, we must have 80 overs and then the last hour would start.
That would be 5pm or later, though never before then.