What happened in 1771 during a cricket match between Chertsey and Hambledon which led to a change in the Laws of Cricket and set the maximum width of a cricket bat at four and a quarter imperial inches?

A player by the name of Thomas White brought a bat whose width was the same as that of the wicket.

By cricket laws, this makes it almost impossible to get him out: He could hold the bat near vertically directly in front of the wicket (which stops him from being bowled) and deflect all balls he can't hit for profit into the ground (prevents being caught). Of course he can't score runs this way either, but he could just be patient and strike only at the worst of deliveries for boundaries.

https://www.theguardian.com/sport/2015/sep/22/the-spin-thomas-daddy-white-super-blade-pioneer