Minnie Harrison was a psychic medium of the middle of the 20th century. She allegedly could manifest a milky white substance known as "ectoplasm" from her body. Below are some vintage images of her work:
First photo: Minnie Harrison while in trance and under very low light conditions, manifests ectoplasm from the mouth. The ectoplasm was attached to a trumpet which ghosts were purportedly able to speak through. This photo was taken by infrared camera.
Second photo: Another photo of the ectoplasmic stuff exuding out of psychic medium, Minnie Harrison. Minnie was an English, spiritualist psychic-medium who claimed she could manifest items from beyond during the mid-1940s through the mid-1950s.
The ectoplasm looked more like gauze, or some type of cloth. Was it real? You decide...
For more about this topic, see: Mediums & Ectoplasm