Talk about a family who was familiar with the fourth dimension! Charles Hinton, author of this interesting essay, married Mary Ellen, daughter of Mary Everest B

Talk about a family who was familiar with the fourth dimension! Charles Hinton, author of this interesting essay, married Mary Ellen, daughter of Mary Everest Boole and George Boole. Mary Ellen's sister, Alicia Boole Stott (http://www.ams.org/publicoutreach/feature-column/fcarc-boole http://www.ams.org/publicoutreach/feature-column/fcarc-boole) "was first exposed to geometric models by her brother-in-law Charles Howard Hinton when she was 17, and developed the ability to visualise in a fourth dimension." She invented the word polytope. Charles Hinton was quite the inventor, he first set up a 3D grid of rods for children to play in and develop Cartesian thinking; this became the jungle gym, which his son, Sebastian, patented. He also invented a gunpowder powered pitching machine to train baseball players (https://www.atticpaper.com/proddetail.php?prod=1897-charles-hinton-pitching-machine-article https://www.atticpaper.com/proddetail.php?prod=1897-charles-...), after causing more than a few injuries had to be retired. He's the great-grandfather of Geoffrey Hinton. In his book The Fourth Dimension (https://archive.org/details/fourthdimension00hintarch https://archive.org/details/fourthdimension00hintarch) he shows how to build models for one to think in 4D, starting on pg. 230.