Psychometry began as a piece of nineteenth-century American physiology rather than spiritualism. Joseph Rodes Buchanan, a professor interested in the physical basis of mental states, coined the term in 1842, literally "soul measuring," after reporting that certain of his students, holding a sealed vial containing an unnamed drug, could correctly describe sensations matching the drug's known physiological effects. Buchanan believed objects retained a kind of impression of everything they had contacted, readable by a sufficiently sensitive nervous system.
The idea was taken up and extended by William Denton, a geology professor, who from 1854 enlisted his sister Ann Denton Cridge to hold cloth-wrapped mineral and archaeological specimens and describe scenes she associated with them, publishing the results in his 1863 book The Soul of Things. Psychometry moved quickly into spiritualist practice, where a medium holding a deceased person's ring or watch to "read" it for the bereaved became a standard séance technique, and the idea persists today in some self-described psychic detectives who claim to read case details from an item connected to a crime or missing person, a practice with no documented record of investigative success beyond chance and generalisation.