Carlos S. Alvarado, PhD, Visiting Scholar, Rhine Research Center
Although ectoplasm is not widely discussed today in the parapsychological literature, this was not the case in the old days. One example, among many, was French physician’s Gustave Geley’s (http://www.aeces.info/Legacy-Section/Bios-1_Scientists/Geley_G.pdf) article “L’Ectoplasmie” (Revue Métapsychique, 1921, No. 7, 355-361).
According to Geley ectoplasm was formed from matter projected from the body of a medium, an idea that preceded him. He wrote in the article that while the medium was in trance “part of her organism is exteriorized,” being an extension of the medium’s body, an exteriorization of its vital force that eventually was reintegrated into the body. Such ideas of vital, psychic or nervous forces have a long history, and precede psychical research. (http://www.medicine.virginia.edu/clinical/departments/psychiatry/sections/cspp/dops/staff/publicationslinks/Alvarado-Human-Radiations-JSPR-2006.pdf).
Geley stated that ectoplasm may change to forms having “all the anatomical and physiological capabilities of living biological organisms.” But in its raw form it could be seen as a “solid substance . . . formed by a protoplasmic amorphous mass” and as a misty-looking substance. Other forms have been reported but Geley focused on these.
He also discussed similarities between ectoplasm and more familiar biological phenomena. These included the hystolisis of insects (the formation and “dematerialization” of tissue), as well as similarities between ectoplasmic luminosities and bioluminiscence, ectoplasmic and protozooic pseudopods, and common ideoplastic processes, or the concept of a guiding principle behind both ectoplasmic and biological processes.
For information about Geley’s ideas and work in English see his books From the Unconscious to the Conscious (Glasgow: William Collins, 1920) and Clairvoyance and Materialisation (London: T. Fisher Unwin, 1927).