Changing the net
The nets got dirty and damaged in the sea. It was believed that a dirty net would not fish as well as a clean net: if the net were damaged then fish might escape through any holes.
The weekly closure meant that the dirty leaders were slapped each week and replaced on Monday with clean nets. The six “heads” would be changed weekly. The dirty head removed and a clean head put in its place.
In a usual week one head would be changed each day but with two done on a Wednesday. If the sea was too rough or the wind too strong then the net change would have to be postponed to another day.
It took about an hour to change a head. It was quite a complex operation that used the flow and force of the tide to its advantage. Despite this it was still heavy work to heave all the ropes and lines tight. These were fishing boats with no hydraulics, purely muscle power.