https://en.wikipedia.org/wiki/Pet_doorA pet door or pet flap is a small portal in a wall, window or human door to allow pets to enter ... The Oxford English Dictionary records the first use of the phrase "
Did you know... when Turner’s cats needed to exit his studio, he decided to cut a hole in this artwork and use it as a cat flap? 🐱
See the (repaired) canvas now on display at Tate Britain:http://ow.ly/o7sY303Nnrx
Joseph Mallord William Turner, 'Fishing upon the Blythe-Sand, Tide Setting In', exhibited 1809⠀⠀