Preliminary Report of the Commission Appointed by the University of Pennsylvania to Investigate Modern Spiritualism: In Accordance with the Request of the Late Henry Seybert

In Short

Formed through a university bequest to evaluate the claims of 19th-century Spiritualism, a panel of skeptical professors systematically tests celebrated mediums. Across controlled séances involving independent slate-writing, spirit-rappings, sealed letters, and dark-cabinet materializations, the investigators detail the precise mechanical tricks, misdirection, and evasions used to fabricate supernatural phenomena. The text stands as an enduring early artifact of scientific debunking, balancing methodical observational notes with dry, sharp satire.

The Story

The account opens with the mandate of the Seybert Commission, established by the University of Pennsylvania to evaluate Spiritualist manifestations. The panelists—including Acting Chairman Horace Howard Furness, Secretary George S. Fullerton, and distinguished professors like Joseph Leidy—begin their work by inviting local and national mediums to demonstrate their powers under simple, controlled conditions. From the start, the investigators encounter a consistent pattern: the moment rigorous scientific observation is introduced, the spirits grow silent.

Initial investigations focus on "independent slate-writing," where spirits supposedly write messages inside bound or held slates. Testing medium Mrs. S.E. Patterson, the committee waits hours while sealed slates yield nothing, though faint rappings sound nearby. When the panel tests Mrs. Patterson standing on glass tumblers—an arrangement meant to isolate electrical or physical vibrations—they discover that the sounds emanate from her vicinity anyway; Furness notes that while her foot remains still, an unusual pulsation is directly feelable within her shoe.

Moving to renowned slate-writer Dr. Henry Slade, the commission sets up sittings in a hotel room. Slade flatly refuses to work with slates sealed shut with screws, claiming the spirits forbid it due to past trickery by skeptics. The investigators observe how Slade demands slates be held out of direct sight under the table leaf, where the edge of a fresh pencil, a hidden hand, or a hastily manipulated accordion can operate unseen. When an investigator accidentally catches a glimpse of prepared slates hidden behind the table, Slade abruptly halts the demonstration. Later, as the medium signs his fee receipt, a panelist kicks over the hidden slates, exposing pre-written messages that Slade frantically washes away.

The inquiry expands to sealed-letter tests and materialization séances. Furness sends sealed envelopes stitched with silk threads to a mail-order medium, Dr. James V. Mansfield; the returned letters show obvious signs of altered paper and cut seals, while those with unmanageable stitching are returned unanswered with a claim that the spirits refused to speak. In physical séances, Secretary Fullerton documents darkness, curtained "cabinets," and fake spirit figures speaking in theatrical voices, accompanied by the suspicious movement of the medium's limbs under dim lighting. Fullerton also re-evaluates famous European tests, demonstrating that earlier favorable reports by foreign scientists suffered from poor vision, uncritical trust, or outright flawed reporting.

The report concludes that the manifestations examined represent gross fraud perpetrated upon an uncritical public. Furness closes the narrative with a reflection on the true nature of belief, expressing hope that Spiritualism will eventually shed its crude, mechanical parlor tricks in favor of higher philosophical pursuits.

How It Unfolds

The mandate is established The commission convenes under the terms of the Seybert bequest to apply systematic empirical tests to modern Spiritualism, issuing an open invitation to practicing mediums while outlining the basic protocols for observation.

The slates remain blank Initial experiments with Mrs. Patterson and Dr. Henry Slade fail whenever slates are locked or sealed; the investigators observe that spirit activity occurs only when slates are hidden from direct human gaze beneath table leaves.

The physical tricks are unmasked Through hidden mirrors, sudden movements, and close physical observation, panel members catch mediums manipulating slates with long fingers, producing raps with their feet, and concealing prepared messages behind furniture.

The mail-order spirits fail Furness tests sealed-letter mediums using hidden silk threads and mucilage safeguards, proving that envelopes are routinely opened, read, and resealed, while secure envelopes are returned with excuses.

The cabinet illusions collapse Observations during dark-room séances reveal how mediums free their hands from physical restraints, manipulate musical instruments behind curtains, and rely on dim lighting to pass off crude drapery as materialized spirits.

The final verdict is delivered The commission members synthesize their logbooks, concluding that every tested phenomenon reduces to jugglery and fraud, while challenging believers to abandon mechanical trickery.

The People

• Horace Howard Furness: The Acting Chairman of the commission, who approaches the investigation with urbane patience and sharp, good-humored satire. He wants to uncover genuine psychological or spiritual truths, but his careful physical tests repeatedly reveal mundane trickery, leaving him amused yet thoroughly unconvinced.
• George S. Fullerton: The Secretary of the panel, who maintains meticulous, immediate notes of every séance. Driven by a desire for uncompromising evidentiary rigor, he methodically catalogs time intervals, physical setups, and evasive maneuvers, ultimately concluding that the movement is a spectacle of gross fraud.
• Joseph Leidy: A distinguished professor on the commission who attends numerous sittings in search of honest evidence. He documents the grammatical flaws, inconsistent handwritings, and absurdities of spirit messages, remaining open to proof while finding only deceptions.
• Dr. Henry Slade: A famed slate-writing medium who attempts to convince the panel of his supernatural connections. He tries to control the testing conditions by claiming spirits refuse to write on sealed slates or under direct observation, but his efforts are undone when his prepared slates and physical manipulations are spotted.
• Dr. James V. Mansfield: A medium specializing in answering sealed letters for a fee. He seeks to maintain a lucrative mail-order practice, but his operation is exposed when he fails to open securely stitched envelopes.

In Its Own Voice

"Indeed Mr. Hazard once told us that the true spirit in which to approach the study of Spiritualism is 'an entire willingness to be deceived.'"

This statement, cited in the preliminary report, highlights the fundamental conflict between the scientific skepticism of the commissioners and the uncritical acceptance demanded by the mediums.

"I have been forced to the conclusion that Spiritualism, as far at least as it has shown itself before me... presents the melancholy spectacle of gross fraud, perpetrated upon an uncritical portion of the community..."

Secretary Fullerton summarizes his immediate findings after months of observing sittings, capturing the panel's overarching verdict in his formal notes.

"Spiritualism, pure and undefiled, if it mean anything at all, must be something far better than Slate Writing and Raps."

Writing in the report's conclusion, Furness reflects on the poverty of physical manifestations, urging a shift away from parlor trickery.

What It's Really About

The report is fundamentally an investigation into the scientific method's encounter with human credulity and deception. Beyond the physical unmasking of slate tricks and fake cabinet apparitions, the text explores the psychology of belief—specifically how the desire for spirit contact leads followers to demand conditions that make genuine verification impossible.

The authors contrast the rigor of empirical observation against the evasive logic of Spiritualist mediums, who claim that the very presence of a critical eye destroys spiritual force. In doing so, the report argues that physical Spiritualism relies not on mysterious cosmic forces, but on basic prestidigitation, selective memory, and an audience's willingness to suspended critical judgment.

Why Read It Today

This report offers a fascinating, firsthand glimpse into late 19th-century American culture, capturing the height of the Spiritualist craze through the eyes of unflinching academic skeptics. Readers who enjoy Victorian history, the history of science, or the literature of stage magic and debunking will find it absorbing.

The text reads like a set of detective logs mixed with dry comedic observation. Horace Howard Furness's commentary carries an enduring literary charm, treating absurd séance encounters—such as spirits who speak only in broken English or Indian "braves" who dominate dark cabinets—with polished irony.

The primary difficulty for modern readers lies in the detailed, repetitive nature of the experimental logs. Pages are devoted to exact table measurements, sitting positions, and minute descriptions of slate construction. However, these meticulous details are precisely what give the book its weight, providing a clear, unvarnished look at how scientific inquiry dismantles elaborate illusions.