Complex sentence: In 1891 at a public séance with twenty sitters the medium Cecil Husk was caught leaning over a table pretending to be a spirit by covering his face with phosphor material.
Split into simpler sentences: In 1891 at a public séance with twenty sitters the medium Cecil Husk was exposed as a fraud. He was caught leaning over a table pretending to be a spirit by covering his face with phosphor material.