Carlos S. Alvarado

Abstract

One of the oldest explanatory concepts of psychic phenomena holds that biological forces are projected from the human body. The old literature refers to this force as animal magnetism, ectenic force, fluids, human radiations, magnetism, nervous force, od, psychic force, and vital energy. This tradition of concepts of force associated with the human body has a history coming from antiquity, and was particularly prominent in the mesmeric movement between the eighteenth and the nineteenth centuries (Amadou, Revue Métapsychique, 1953, No. 21, 5-33). The use of the concept of the "fluid" to explain parapsychological phenomena represents an attempt to give a physical, mechanical, and natural explanation to unexplained phenomena. This has been a recurrent theme in discussions of these forces, especially in terms of relating them to neurological ideas or to other phenomena of nature.

Franz Anton Mesmer presented twenty-seven propositions about animal magnetism in his Mémoire sur la Découverte du Magnétisme Animal, published in 1779. The so-called mesmeric trance, and such other phenomena as the transposition of the senses and healing, was attributed by many to "animal magnetism." Later mesmerists - among them James Esdaile - continued this tradition. Reformulations of the concept of animal magnetism appeared in the works of Karl von Reichenbach, who postulated a universal force he called od.

During the heyday of spiritualism many writers speculated about spiritualistic phenomena offering concepts of bodily forces as explanations. Influential books such as Rogers' Philosophy of Mysterious Agents (1853), and Dods' Spirit Manifestations Examined and Explained (1854) postulated that a nervous force could be exteriorized from the body to account for mental and physical phenomenon such as movement of objects, materializations and telepathy.

Later psychical research developed these concepts further, especially in the face of the phenomena of physical mediumship. A common idea was that these phenomena arose from the action of a biological energy dependent on the body of the medium, a clear extension of earlier concepts from mesmerism and spiritualism. As argued by Hereward Carrington: "It is this energy which moves material objects in the immediate vicinity of the medium (telekinesis) and is capable of being moulded or manipulated into hands, heads, and phantasmal forms, by means of the subconscious mind of the medium, or by the mind of some external entity (materialisation)" (Psychic Research Quarterly, 1921, 1, p. 273). Among the writers who discussed these ideas of force were Hereward Carrington, W.J. Crawford, Edward W. Cox, Albert de Rochas, Gracis Gerry Fairfield, Cesare Lombroso, Joseph Maxwell, Enrico Morselli, F.W.H. Myers, and Julian Ochorowicz.

With the rise of the Rhinean paradigm these ideas were set aside by mainstream psychical research. The new experimental parapsychology presented results seemingly inconsistent with the workings of a biological force, namely the apparent independence of psi phenomena from any physical parameters. Nonetheless these ideas of psychic forces are still common, especially in a variety of healing and metaphysical systems, and in the popular culture.

Acknowledgements

This paper was possible thanks to the rich library resources of the Eileen J. Garrett Library at the Parapsychology Foundation. I wish to thank Nancy L. Zingrone for useful editorial suggestions for the improvement of this paper. The paper is dedicated to the memory of Arthur J. Ellison whose critical writings on the detection of subtle energy serve as a reminder of the methodological difficulties in this field (see Ellison, 1962, 1967, 1982). For correspondence about this paper write to the author at: Division of Personality Studies, Department of Psychiatric Medicine, University of Virginia Health System, P.O. Box 800152, Charlottesville, VA, 22908, email: csa3m@uva.edu

One of the oldest explanations of psychic phenomena hold that seemingly paranormal mental and physical effects are accomplished by means of a force projected from the body of a person. This force has been called by many names: animal magnetism, ectenic force, fluids, human radiations, magnetism, nervous force, od, psychic force, telergy, and vital energy. In this paper I will briefly review aspects of the literature of this concept.¹ I am not concerned here with the physical reality of these concepts of force nor with their value as theoretical models. I am limiting my discussion to the ideas of the proponents, and I will not get into the literature that criticizes these ideas. I recognize, as historian of human radiations Julio Ungaro (1992) has argued, that science (or parapsychology) has never officially accepted the existence of this phenomenon. ² For pragmatic reasons I am also focusing only on Western developments, on the period from the last decades of the nineteenth century to the 1930s, and only on those discussions which centered on psychic phenomena. This means I will not get into such areas as the controversial N rays or other radiations discussed outside of the mesmerism, Spiritualism and psychical research literatures (for overviews see Bischof, 1995/1998; and Ungaro, 1992). ³

Nineteenth Century Mesmerism and Spiritualism

Human radiations, "fluids," psychic forces and the like were proposed as the method by which psychic phenomena were produced. The "force" - conceptualized as a kind of biological magnetism or electricity - supposedly served as a carrier of information and as the agent behind physical action exteriorized from the body. The use of "force" to explain parapsychological phenomena, Amadou (1953b) noted, represented an attempt to give a physical, mechanical, and natural explanation to unexplained phenomena. This attempt to naturalize psychic phenomena has been a recurrent theme in discussions of these forces.

Perhaps the best known concept of this sort was the "fluid" popularized by the mesmeric movement. As one representative of mesmerism wrote:

As we cannot comprehend how a body can act upon another at a distance, without there being something to establish a communication between them, we suppose that a substance emanates from him who magnetizes, and is conveyed to the person magnetized, in the direction given it by the will. This substance, which sustains life in us, we call the magnetic fluid. The nature of this fluid is unknown; even its existence has not been demonstrated; but every thing occurs as if it did exist, and that warrants us in admitting it . . .. (Deleuze, 1852, pp. 1-2)

Franz Anton Mesmer (1734-1815) discussed these ideas in his writings. For example, in his Mémoire sur la Découverte du Magnétisme Animal, published in 1779, Mesmer presented twenty-seven propositions about "a universally distributed and continuous fluid, which is quite without vacuum and of an incomparably rarefied nature, and which by its nature is capable of receiving, propagating and communicating all the impressions of movement . . . ." (Mesmer, 1779/1970, p. 54). This fluid, which Mesmer called animal magnetism, was related to physical and organic matter, the human body being affected by it through the nerves. In a further attempt to relate this force to other aspects of nature, Mesmer argued that in the human body this agent "has properties similar to those of the magnet; different and opposite poles may likewise be distinguished, which can be changed, communicated, destroyed and strengthened. . . ." (Mesmer, 1779/1970, p. 55). In addition, Mesmer argued that animal magnetism could be affected by the heavenly bodies and by the action of the fluids of surrounding persons. Its actions could be communicated to organic and inorganic matter, transferred at a distance, made to penetrate bodies, intensified and reflected by mirrors, stored up in other substances and organic matter, and used for medical cures.

Darnton (1968), a historian of mesmerism, has reminded us that ideas of animal magnetism were developed by Mesmer and others in France in the context of a great interest in all kind of physical forces. At the time, the wonders of electricity were as mysterious to the intellectual and scientist as was animal magnetism. In this context, animal magnetism was only one among many unexplained forces of nature. While this context did not ensure universal acceptance of the idea of animal magnetism in all quarters, it did prepared the ground for receptive hearing.

The mesmeric force was thought to be transmitable through magnets, a steady gaze, and through the well-known magnetic passes. Historians of mesmerism noted that this fluid was considered by many to be the agent behind such paranormal phenomena as the induction of trance, the community of sensation, (in which the entraced person was in mental contact with the mesmerizer and could obey his commands without verbal induction), cures, clairvoyance, and the phenomena of transposition of the senses (in which the mesmerized person could see or perceive from parts of the body such as the pit of the stomach).⁴ For one follower of Mesmer this latter ability was attributed to the influence of "animal electricity," an agent that could transfer sensory impressions to the nervous system in the absence of receptor organs such as eyes (Pététin, 1808).

An anonymous writer in an article published in the July 1867 British journal Human Nature summarized the assumptions of some of the mesmerists regarding this fluid:

The general opinion among mesmerists as to the nature of the agent is, that it is a fluid generated by the nerves-and ethereal, vital spirit or essence, which penetrates all bodies,--on the due development and proper distribution of which health and life depend . . . . The fundamental fact in mesmerism may be said to be, that the nervous system of one man is capable of being acted on by that of another . . . . (What is Mesmerism?, 1867, p. 228).

Many writers developed this idea that animal magnetism was connected with vital processes of the body. To some extent, such ideas were a normal outgrowth of neurophysiological ideas prevalent in the eighteenth century (Brazier, 1984; Jackson, 1970). These ideas held that fluids and forces that flowed through the nerves, allowed for movement and for the processing of sensory impressions. Following this tradition, British physician James Esdaile (1808-1859) argued that a nervous fluid carried the orders of the brain within the body, and that this fluid was also involved in perception. This fluid could produce mesmeric phenomena. For example, Esdaile argued that the fluid "is transmitted to the mesmerised person's brain through the medium of his nerves: and the consequence is, that the thought-modified nervous fluid of the active brain is both reflected and understood by the passive brain of the patient, exactly as the passive end of an electric telegraph records the impulses received from the active extremity of the battery . . . ." (Esdaile, 1852, p. 238). For Esdaile and others such idea could account for the transmission of thought at a distance, or the influence of the mesmerizer over the mesmeree without apparent conventional sensory commands.

To some extent, then the concept of animal magnetism was intimately related to these ideas of nervous force. In fact, some mesmerists seemed to have conceptualized both as one and the same force (e.g., Esdaile, 1852; for a review and for exceptions see Gauld, 1992).

While the idea that animal magnetism could induce trances and produce what we call now the phenomena of hypnosis was particularly popular during the latter part of the eighteenth century and the first half of the nineteenth, the concept by no means disappeared in later periods. For example, Edmund Gurney (1847-1888), one of the most creative members of the Society for Psychical Research, conducted experiments designed to show a mesmeric influence that was separate from suggestion (e.g., Gurney, 1884). Later magnetic practitioners continued this work and maintained alive the idea of a fluid as a causal agent behind the hypnotic trance, healing phenomena, and other psychic experiences (e.g., Jagot, n.d.). For example, papers presented in a 1923 "experimental psychology" congress included such titles as "The Action of Human Radiations on Microbes," "The Therapeutic Action of Magnetism," and "The Motor Action of the Magnetic Force" (Durville, n.d.). Other late mesmerists continued to defend the concept of animal magnetism in the induction of trance and other phenomena (e.g., Alrutz, 1922; Boirac, 1908/1918).

The mesmeric movement influenced Baron Karl von Reichenbach (1788-1869) to study the hypothetical force he called od. ⁵ Like the mesmerists, Reichenbach (1849/1851) considered od to be a universal force. In his view, od was not only generated by the human body, but also by magnetism, crystals, light (including sunlight and moonlight), heat, friction, chemical processes and electricity, among other causes. In the human body such processes as digestion and respiration produced od. Sensitive persons, Reichenbach thought, were able to perceive this force in different ways, such as visually (e.g., lights and auras around magnets, crystals and individuals) and as sensations of temperature and discomfort. In his discussion of the properties of od Reichenbach stated:

It is conductible through all other bodies; it is capable of being either directly accumulated on, or transferred by distribution to other bodies; it disappears from them in a short time; . . . it is arranged in a polar manner in animal bodies . . . ; it is without appreciable relation to the terrestrial magnetism; it is capable of mechanically attracting the hands of cataleptic patients . . . . (Reichenbach, 1849/1851, p. 116).

Colonel Albert de Rochas (1837-1914) popularized Reichenbach's work and reported his own observations in his book Le Fluide des Magnétiseurs (1891). Following Reichenbach, de Rochas considered od a vital principle, a force intimately connected with the human body and its functions. He considered the brain and its ganglions to be the main centers of od in the human body. As he wrote in his 1891 book:

The odic movement, called a current, comes mainly from the brain, descends down through the nerves of the face and goes to its corresponding ramifications. Finally, it is exhalled in the air, rendered sensible by impressions of heat and cold that it causes on the sensitives, is made visible in the form of effluvia in plain day, and as lights in darkness. The whole body seems bright; the head seems to have an aureole; the hands, the fingers and the toes throw long streams of odic light (p. 104, my translation).

De Rochas wrote about the "existence in the human body of a force similar to electricity and capable of projecting itself out of it . . . ." (De Rochas, 1887, p. 387, my translation). In his books L' Extériorisation de la Sensibilité (1895) and L' Extériorisation de la Motricité (1896) he argued that human being's capacity to perceive and to cause movement could function outside of the body, thus producing phenomena such as perceiving at a distance and movement of objects without contact.

Drawing from the ideas of the mesmeric movement and from Reichenbach's work many individuals speculated about the causes of spiritualistic phenomena using these concepts of bodily forces. Influential books such as Rogers' Philosophy of Mysterious Agents (1853), and Dods' Spirit Manifestations Examined and Explained (1854) postulated that a nervous force could be exteriorized from the body to account for mental and physical phenomenon such as movement of objects, materializations and telepathy. So, for example, Dods argued that the body's "electro-magnetic" forces were related to the "involuntary powers in the back of the brain. . . ." (Dods, 1854, p. 33), the section of the brain thought to control involuntary body functions.

Another interesting example which linked physiological forces to spiritualistic phenomena was an article by an anonymous writer published in 1855 in the magazine North American Review. This author believed that an electromagnetic current constituted the vital aspect of the human organism. He wrote:

The vertebrae are, as it were, the successive plates of a galvanic battery, of which the skull is the apex, while the spine, culminating in the brain, constitutes, like the acid in the artificial battery, a continuous and cumulative creator and channel of the electromagnetic force. Of this force the nerves of sensation and of voluntary motion are the conductors. . . . The living battery, as ordinarily charged, may suffice to keep but one hemisphere of the brain in action, while an excessive charge may keep both hemispheres in simultaneous action.

This theory may account for the rappings, phosphoric lights, table tippings, and other physical phenomena, reported in connection with the pretended spiritual intercourse.  (Modern Necromancy, 1855, p. 521)

The ideas of British Serjeant-at-law Edward W. Cox (1809-1879) on what he called a "psychic force" were particularly interesting and influential. Cox described his idea mainly in two books: Spiritualism Answered by Science (1872), and What Am I? (1874). Like previous writers, Cox argued that a force emanated from the nervous systems of Psychics (his term). This force, directed by the Psychic's intelligence, produced the physical phenomena of spiritualism. He wrote:

The Psychic is a person in whom there is an abnormal capacity for dislocation in the normal relationship of Soul and body. In such a condition, the Soul (or Psychic) Force ceases to flow through its usual channels and therefore manifests itself without them, as does the magnetic force, in disturbing effects upon molecular structure. Psychic Force . . . penetrates and permeates molecular matter; and . . . neutralises in matter the force of gravity. (Cox, 1874, pp. 417-418)

According to Cox this force normally is related to such body processes as movements. But the mediumistic trance was a catalyst in breaking the normal balance of the force and allowing it to leave the body. In another book, he wrote: "As the organism is itself moved and directed within its structure by a Force . . . it is an equally reasonable conclusion that the Force which causes the motions beyond the limits of the body is the same force that produces motion within the limits of the body " (Cox, 1872, p. 101; on this topic see Alvarado, 1981).

Cox influenced English physicist William Crookes (1832-1919), who performed experimental studies of the psychic force with celebrated and influential medium D.D. Home (1833-1886) (Crookes, 1874b). In Crookes' view the effects produced by Home were due to a psychic vital force. Crookes observed how physically exhausted Home was after some tests, something noticed repeatedly throughout the literature of physical mediums. Both Cox and Crookes observed the variations in the psychic force, a power that had its ups and downs in terms of intensity. The materializations of human forms, also seemed to invoke the notion of a variable psychic force, a phenomenon Crookes (1874a) studied and photographed. An example with the famous and extremely controversial English medium Florence Cook (1856-1904) was the observation that "the spirits . . . have often a pale, ghastly look, as usual when the power is weak" (Spirit Faces, 1873, p. 83, my italics).

Gracis Gerry Fairfield in his book Ten Years with Spiritual Mediums (1875), also attempted to relate psychic forces to the nervous system. Fairfield defended the existence of a "nerve-aura," a force he defined as "an emanating atmosphere having the molecular properties, motor and sensory, of nervous tissue itself, though of lessened intensity" (Fairfield, 1875, p. 122). Such a substance, Fairfield thought, could account for both the mental and the physical phenomena of Spiritualism. The author believed that the release of this force was associated with molecular disturbances of nerve-centers. Fairfield discussed epilepsy as an example of the pathological excitation of the nerve-centers, and as a disease involving the same molecular disturbance involved in the release of nerve force from the body.

In an attempt to explore the properties of this force, Fairfield experimented with nebulous formations he saw close to mediums. As he explained:

At a séance . . . I attended, removing the arm of a horseshoe magnet, I brought the open poles in contact with the nebula, with a view of testing whether it could be dissipated in that way. The test was not successful from that aspect of the subject; but it was quite successful from another point of view . . . . The poles of the magnet being advanced toward the border of the nebula, the medium, who was sitting about six feet from it . . . was attacked with perceptible convulsions of tetanic cast. On closing the armature, the convulsions ceased. Though not dissipated by magnetism, the nebula also was perceptibly agitated to and fro, and developed augmented light. I now tested the matter further, by removing the arm of the magnet at other points in the room contiguous to the medium, but no perceptible effect on his nerves was developed. I regard this test as conclusive evidence that the nebula was in this case a transformation of the nervous atmosphere of the medium, and that the magnetism that produced the slight spasms was transmitted to the medium's nerves through contact with this nervous nebula, suspended in the atmosphere fully six feet from his person (Fairfield, 1875, pp. 149-150).

Like Fairfield, the Reverend Asa Mahan explained spiritualistic phenomena as resulting from a force generated by the human body, and did not accept the concept of discarnate agency (Mahan, 1855, 1875). The force could be intelligent or not according to its locus in the nervous centers:

When such centre is not immediately connected with the brain, then the action of this force, like that of magnetism, is simply that of a repulsive and attractive power, without the characteristics of intelligence. When that centre is the brain, then the direction of the action of this power bears, in many important particulars, the characteristics of intelligence, the action of the force, in such cases, being not only in accordance with, but evidently directed by, mental states (Mahan, 1875, pp. 96-97).

A somewhat different concept was presented by Allan Kardec (the pseudonym of Léon Hyppolyte Denizard Rivail, 1804-1869). Kardec, considered by many as the codifier of spiritist doctrine, popularized the concept of the perispirit in writings he published between the 1850s and the 1860s (e.g., Kardec, 1861/1874). He followed the teachings of the spirits as "dictated" through mediums. These teachings asserted that the constitution of human beings consisted of the soul or spirit, the physical body, and the perispirit, "a fluidic envelope, which is semi-material, and constitutes the link between the soul and the body" (Kardec, 1861/1874, p. 53). The perispirit is the "means by which the spirit acts upon its fleshy organs and transmits its will to all that is exterior to itself" (Kardec, 1861/1874, p. 54). According to Kardec, it is through the perispirit that discarnate spirits of the dead can appear as apparitions, as materializations, and can move objects. In a physical medium, the fluid of the perispirit is strong and emanates from the body. As Kardec described the process following the teachings of the "spirits":

When an object is set in motion, carried away, or raised into the air, the spirit does not seize it, push it, or lift it, as we do with our hands; the spirit, so to say, saturates it with his own fluid combined with that of the medium, and the object, being thus vivified for the moment, acts as a living being would act . . . [and] it follows the impulsion communicated to it by the will of the spirit (Kardec, 1861/1874, pp. 76-77).

Followers of Kardec, such as the French engineer Gabriel Delanne (1857-1926), discussed further the role of the perispirit in human affairs and in the production of psychic phenomena (Delanne, 1923, Part 4; see also Fedi, 1937). Another writer said:

The perispirit . . . radiates a complex of rays and if it is in perfect harmony with the physical body, they find a free outlet beyond its limits; but if the physical body is unable to transmit the rays, they accumulate round the perispirit, producing a series of disturbances in both the psychical [the perispirit] and physical bodies, which may end in serious illnesses, such as neurasthenia, nervous swellings, &c. (Kudriavtzeff, 1909, p. 175).

Many of the individuals mentioned before suggested that materialization phenomena were caused by this invisible energy. Such ideas were consistent with the speculations that "invisible exudations from the human organisations" were used by spirits to create visible and tangible forms (Owen, 1871, p. 404). The spirits, according to another writer, "through the exercise of their united will-power attract and gather certain magnetic and material elements from the medium, the persons present, and the atmosphere . . . ." (Crowell, 1879, pp. 181-182). Similarly, Brackett (1886, pp. 126-127) referred to luminous vapor as the matter from a medium's body to create materializations. ⁶

The Russian Imperial Counselor to the Czar and psychical researcher Alexander Aksakow (1832-1903) wrote that all materialization involves dematerialization, or the apparent use of matter from the body of the medium (Aksakow, 1894-1895/1896).⁷ Aksakow believed there were three stages of materializations. The first consisted of movement of objects, and touches caused by an invisible force. The second consisted of visible and tangible, but incomplete forms such as hands, heads and busts. Finally, the third one was complete materializations, with the production of whole bodies. These stages - in Aksakow's view - were related to forces coming from the medium's body, a point he illustrated in his book with the case of the partial dematerialization of the body of medium Elizabeth D'Esperance (1855-1919). The assumption was that the medium's psychic force was transformed into the matter needed for materializations.

During the nineteenth century (and later) there were many attempts to record human radiations using photographic plates (for reviews see Girod, 1912; Krauss, 1995; Ungaro, 1992, Chapter 3). Because photography had been actively used to record materialization and other phenomena, as well as to capture "invisible spirits" around the sitters (see Krauss, 1995), it was logical to expect that photography would also be used to capture invisible human radiations as well. A pioneer in this area was the French Commandant Louis Darget. Darget reported he obtained "effluviographies," or pictures of the "fluid," around hands, fingers, as well as of plants. In addition, he obtained thoughtphotographs by placing photographic plates at a short distance from a person's body (Tégrad, 1902).⁸ The French physician Hyppolyte Baraduc (1850-1909) was another example of this type of work. He presented many pictures of vital radiations taken using a variety of methods, such as prolonged contact of hands with photographic plates (Baraduc, 1896). A variety of human radiations were postulated to explain ESP-type phenomena. Among these were speculations on nerve energy as transmitted by the ether (Crookes, 1898) and the action of "brain waves" (Houston, 1892). ⁹

Concepts of Force in Psychical Research During the Twentieth Century

Later psychical research developed these concepts further, especially in an effort to explain the phenomena of physical mediumship. As in previous literature, the common notion was that of a biological energy dependent on the body of the medium, an idea which was a clear extension of earlier concepts from mesmerism and Spiritualism. One psychical researcher deeply interested in these issues argued: "It is this energy which moves material objects in the immediate vicinity of the medium (telekinesis) and is capable of being moulded or manipulated into hands, heads, and phantasmal forms, by means of the subconscious mind of the medium, or by the mind of some external entity (materialisation)" (Carrington, 1921, p. 273).

Although psychic forces were featured more often in the European literature than in Anglo-American writings, the latter included interesting concepts. One of them were the ideas of British classical scholar and psychical researcher Frederic W.H. Myers (1843-1901), generally known for his interest in the subliminal mind and in survival of bodily death (Myers, 1903). In Myers' views some psychic phenomena were "extensions of vital phenomena which we already know to occur under subliminal control . . . ." (Myers, 1895, p. 21). This included all kind of metabolic processes. In his Human Personality and Its Survival of Bodily Death, Myers (1903, Vol. 2, pp. 505-554) had a section entitled "Scheme of a Vital Faculty." Here he wrote about physical phenomena and about his concept of ectoplasy, or the "extrusion from the organism of vital energy . . . ." (p. 529). The term is defined later as "the power of forming, outside some special organism, a collection or reservoir of vital force or of vitalised matter, which may or may not be visible, may or may not be tangible, but which operates in like fashion as the visible and tangible body from whence it is drawn" (p. 545).

In this discussion Myers was influenced by communications received through English medium Reverend W. Stainton Moses (1839-1892). Based on Moses' "spirit" communicators, Myers discussed the idea that the force may come from other persons present, in addition to the medium (Myers, 1903, Vol. 2, p. 530). In a paper about Moses, Myers (1894, pp. 275-276) cited commentaries about how the power in a séance with this medium was exhausted, so the sitter was told to rub his hands and make passes to generate power. In addition, similar to Kardec and others, Myers speculated on the possibility of disembodied spirits using the vital energy of medium and sitters.

This reference to movements as generators of vital power was one of the observations made by French jurist and physician Joseph Maxwell (1858-1938) in his study of physical mediums. Maxwell, who had extensive experience with many mediums, believed that the force emitted to cause physical phenomena was "kindred to the energy which circulates in our nerves, and which provokes the contraction of our muscles" (Maxwell, 1903/1905, p. 51). To generate this force, Maxwell thought muscular contractions were useful. He wrote, "a movement without contact can be procured by tightly squeezing one another's hands, or by resting the feet very firmly on the floor . . . . " (p. 110). In his experience it was very important to have harmonious conditions in the mediumistic circle, a situation that ensured "the synergy of forces which each member of the circle develops" (p. 49).

Regarding the use of this force, Maxwell believed that there were several markers which indicated its flow and action. One of these was the fatigue felt both by the medium as well as by the sitters and experimenters after a séance, presumably felt because since mediums used the energy of other people present to replace their own expenditure of force when producing telekinetic and materialization phenomena. Other markers mentioned by Maxwell were sensations of: cold breezes, tingling in the hands and fingertips, currents through the body, and spider webs in hands and face.

One of the mediums Maxwell studied was the Italian Eusapia Palladino (1854-1918). As I have argued before (Alvarado, 1993), Palladino was very important for the development of concepts of paranormal forces not only because of the phenomena reported to take place around her, but because she presented all kinds of behaviors (e.g., movements of the hands corresponding to movements of objects, statements about the force, exhaustion after seances) that supported the idea of the emission of a bodily force. While she was not unique in this, her performances were particularly influential in the developments of these concepts of force.

For example, Italian psychiatrist Enrico Morselli (1852-1929) derived his ideas from sittings with Palladino. Morselli's two volume work Psicologia e "Spiritismo" (1908) was largely devoted to the physiology and psychology of Palladino's phenomena. In his view the medium could create phantasms and forms "through the radiant exteriorization of its force, the bio-psychic ondulatory emanation projected" from Palladino (Morselli, 1908, Vol. 1, p. 449, my translation). This force was further described as an "exopsychism, a vital dynamism" (Vol. 1, p. 322, my translation). Like many previous writers, Morselli believed in collective agency to explain this force. In his book he reported that dynamometric readings taken before and after seances showed that the force expended in the hand grip of medium and sitters decreased from the first to the second measurement, suggesting energy expenditure during the séance by all involved (Vol. 1, pp. 351-352; see also Lodge (1894, pp. 326-327).

Morselli went further and argued that the phenomena consisted of more than the projection of this force. In addition, the medium could use her "supernormal perception" to obtain information such as the likeness of a deceased individual from the minds of the sitters. The medium then had the ability to use this information to create the impression that a spirit had materialized, thus producing a materialization or some intelligent sign that could be recognized by the sitters as coming from or representing someone they knew. In turn, this took place through the "oniric" or "subconscious" processes of the entranced medium. In Morselli's view this force was normally regulated by the medium's system to deal with such requirements of life as sensory impressions. In this way Morselli's ideas are similar to those of Cox, de Rochas, and Myers. During trance, according to Morselli, the superior centers of the nervous system controlling the liberation of this energy were inhibited, thus allowing for the flow that produced Palladino's physical phenomena.

Table 1 compiles a list of other researchers who were prompted to speculate on forces or radiations by Palladino's phenomena (see next page).

The idea that emanations could extrude from of the bodies of mediums was also supported by observations of structures apparently coming out from their bodies during seances. The fluidic arms of Palladino were an example. Carrington, commenting on Palladino's American seances, said "we have seen what was apparently a third arm - an arm exactly like Eusapia's own - coming out of her shoulder, and touching the sitters on the right hand side" (Carrington, 1910).

Polish physician and psychical researcher Julian Ochorowicz (1850-1917) conducted particularly influential studies with Polish physical medium Stanislawa Tomczyk (Ochorowicz, 1909, 1910, 1911). Ochorowicz studied the properties of what he called "rigid rays" or ectoplasmic structures that could move small objects. In his 1909 paper he said he observed threads coming from the medium's fingers. According to him he could cut these threads and they would form back again. According to the medium there were different forces at work. She referred to: (1) the personal current of the medium, capable of acting a short distance from the body; (2) the etheric or fluidic hands of the medium's double, which could act at a distance without help from the medium's own force; and (3) the current from the hands of the medium's double, which could act at a short distance from the body (Ochorowicz, 1909, p. 98).

Table 1

Concepts and Observations Related to Forces with Eusapia Palladino

In addition, Ochorowicz (1911) conducted experiments to study the properties of the threads. The "fluidic thread" could carry objects, and could be detected when passing through smoked paper and liquids. The "current" or rays could carry water or humid particles that were able to cause chemical reactions when combined, thus showing the transfer of one substance to another. They were also found to be resistant to fire, unaffected by a magnetic field, and capable of conducting electricity.

The physical mediumship research conducted by Irish mechanical engineer W.J. Crawford (d. 1920) has also been cited frequently in this context. Crawford worked with a mediumistic circle, the Goligher circle, producing such phenomena as table levitations. Crawford conducted experiments that led him to postulate a cantilever theory of table levitations (Crawford, 1916/1918; see also his later studies: Crawford, 1919, 1921). This consisted of the idea that an invisible structure emanating from the body of the medium (but nurtured as well by the psychic forces of the sitters) could levitate tables. In some studies Crawford found that the medium's weight increased when the table was levitated, suggesting that the table's weight was transferred to the medium through an invisible structure projected by her body. In other occasions, Crawford believed that the cantilever had a point of contact on the floor and the weight was not transferred to the medium. In addition, both the medium and the sitters lost weight after the seances. ¹⁰

Crawford believed that invisible "operators" or spirits manipulated the forces in question. Based on statements by these entities, the process was described as follows:

Operators are acting on the brains of the sitters and thence on their nervous systems. Small particles, it may even be molecules, are driven off the nervous system, out through the bodies of sitters at wrists, hands, fingers, or elsewhere. These small particles, now free, have a considerable amount of latent energy inherent in them, an energy, which can react on any human nervous system with which they come into contact. This stream of energised particles flows round the circle, probably partly through the bodies of the sitters, and probably partly on the periphery of their bodies. The stream, by gradual augmentation from the sitters, reaches the medium at a high degree of "tension," energises her, receives increment from her, traverses the circle again, and so on. Finally, when the "tension" is sufficiently great, the circulating process ceases, and the energised particles collect on or are attached to the nervous system of the medium, who has henceforth a reservoir from which to draw. The operators having now a good supply of the right kind of energy at their disposal, viz. nerve energy, can act upon the body of the medium, who is so constituted that gross matter from her body can, by means of the nervous tension applied to it, be actually temporarily detached from its usual position and projected into the séance room. (Crawford, 1916/1918, pp. 242-243)

Table 2 shows several other observations that have been interpreted as support for the concept of a psychic force. These ideas are really the tip of the iceberg. Other concepts I have not discussed because of space constraints include those proposed by Bozzano (1926-1927), Cavalli (1928), de Szmurlo (1924), Fraser-Harris (1934), Gruber (1926), and Sudre (1926), as well as the research of Grunewald (1920), Schrenck-Notzing (1920/1925), and Tanagra (1932/1972), among others. I have also neglected most of the literature about the use of instruments to detect or measure these forces (e.g., Mondeil, 1927; see also Carrington, n.d., pp. 49-56; and Ungaro, 1992, pp. 18-25, 51-55, 58-60, 72-73). But the material discussed in this paper should be enough to give an idea of some aspects of this literature.

Concluding Remarks

The idea of a human radiation has been one of the main explanatory models of phenomena in the history of mesmerism, Spiritualism, and psychical research. This hypothetical subtle energy was considered as the agent behind thought-transference, movement of objects, materializations, healings, and many other phenomena.

Table 2

Additional Observations About Psychic Forces

While there were many differences between the concepts of force discussed in this paper, most of them were clearly conceptualized as biological in nature. In addition, many of these ideas associated these forces to functions of the body such as movement and to life itself (as seen in the ideas of Reichenbach, Cox, Myers and Carrington, among others). Even such concepts as animal magnetism and od, that were considered by Mesmer and Reichenbach to be universal forces, have been described as being housed in the human body and related to its workings as well. In addition, many of the early writings argued that this force was intimately related to the nervous system or that it was the nerve force itself. Esdaile's writings provide an example of this as does those of the anonymous writer in the North American Review, Mahan, Maxwell, and many others. There was clearly an interest in relating such a force to other natural phenomena.

But ideas of force also had a different role, in that they were used to naturalize psychic phenomena. For many, postulating an alternate view of the functioning of the nervous system to explain a variety of mysterious-looking phenomena was important in that the phenomena in question could then be related to the functions of the body, a kind of an extended chapter of human physiology. This seems to have been the thrust behind the writings of Rogers, Dods, Cox, Fairfield, Lombroso, Maxwell, and several others.

The emphasis on physiological explanations was an attempt to combat the notion of discarnate agency. While many saw the phenomena of mediumship (and other phenomena) as the product of the action of the spirits of deceased individuals, others argued that the phenomena could be explained by the psychic faculties of the living, in this case by the projection of a force from the human body. Like the current idea that ESP and PK can explain what seems to be survival phenomena, these ideas of force served as an explanatory concept that could be actively used to combat the basic tenet of Spiritualism. Fairfield, Mahan, and Morselli, among others, were clearly interested in this goal. Nonetheless, others such as Kardec, Lombroso, Myers, Carrington, and Crawford presented views that postulated the action of spirits of the dead. These opposing views have been called "animism" and "spiritism" (Aksakof, 1890/1895) and have defined much of the interest in survival of bodily death in psychical research.

It is also interesting to notice that some of the writers I have mentioned before (e.g., Cox, Fairfield, Morselli, and Carrington) believed that the mind of the medium could guide the phenomena. Ochorowicz, Maxwell and others believed that the minds of the sitters in the circle could affect the shape and type of phenomena obtained. This was a topic discussed by many others in the literature (e.g., Bozzano, 1926-1927; Cavalli, 1928; Lebiedzinski, 1924; Mackenzie, 1923; Schrenck-Notzing, 1920/1925; Sudre, 1926). Another fascinating aspect of these ideas is the frequent allusion to collective agency, that is, to the combination of the psychic forces of mediums and sitters. While these ideas can be traced back to the mesmeric period (and perhaps before), the research with Palladino using dynamometers and Crawford's weighing studies were the first systematic attempts to test this idea (on the concept of collective agency see Mackenzie, 1923; and the later writings of Sudre, 1956/1960; and Warcollier, n.d.).

The ideas discussed in this paper no longer have the currency in the modern research literature of parapsychology that they had in previous times. But they have not completely disappeared either. Some figures from the old period reviewed here -- Carrington (1952-1953), Cazzamalli (1954, 1960), Tocquet (1959), and Sudre (1956/1960) -- have presented the concept to a new generation of researchers. In addition, the interest in Soviet parapsychology, with the concept of bioplasma and such techniques as Kirlian photography, kept alive the idea of vital, biological energies related to psychic phenomena (e.g., Adamenko, 1970; Krippner & Rubin, 1974; Masopust, 1971; Sergeyev, 1972). Such concepts are still discussed both within the parapsychological literature (e.g., Grad, 1989) and particularly in more popular writings (e.g., Motz, 1998). Tiller's writings (1997) have also contributed to the modern articulation of the concept of subtle energies. And we should remember that a variety of such methods of alternative medicine as therapeutic touch, acupuncture, and many massage systems are based on beliefs in forms of subtle energy related to health  (Krieger, 1979; Motz, 1998; Srinivasan, 1988). These issues are the concern of the International Society for the Study of Subtle Energies and Energy Medicine. In addition, the concept is central to the parapsychology of such Asian countries as China (Leping & McConnell, 1991) and Japan (Kokubo & Kasahara, 2000). One also finds the concept discussed elsewhere, such as in Brazil (e.g., Quevedo, 1971).

The rise of modern experimental parapsychology in the Anglo-American milieu decreased interest in the concept of human radiations. ¹¹ The work of J.B. Rhine and associates redefined modern parapsychological research. The new experimental parapsychology (or at least some of its representatives) claimed that time and space were irrelevant to ESP and PK test performance (for statements about this see Rhine, 1947; Rhine & Pratt, 1957). Within this view, closely related to Rhine's (1947, 1953) dualistic assumptions, old concepts of psychic forces and research seemed to lack explanatory power and became characterized as part of a primitive period of the history of parapsychology. Undoubtedly there were also other factors in the decline of the notion of force such as the taint of fraud surrounding physical mediumship. In addition, the notion of psychic forces is inconsistent with more recently developed concepts of non-locality (e.g., Oteri, 1975; Varvoglis, 1986). ¹²

Modern parapsychologists probably will want to see whether some of the old research (such as that of Crookes, Ochorowicz and Crawford) may be replicated with better instrumentation and controls. From the point of view of those of us who are interested in the history of ideas, much more needs to be done to trace the development of these concepts, their relationship with ideas about physical forces prevalent at the time in which they were developed (neurophysiological concepts, electricity, radioactivity, X rays, radio waves), their relationship to other variables (e.g., distance), and to other such conceptual traditions as vitalism (e.g., Carrington, 1921; Driesch, 1924/1925; Geley, 1919/1920; Myers, 1903). In addition, there is much to explore regarding the maintenance of such ideas. This has been described to some extent in another paper (Alvarado, 1993), in which I argued that ideas of human radiation are not wholly derived from research results, but are also connected to other non-scientific aspects such as the behaviors of mediums during the seances. Historians of ideas will also be interested in the reception of these concepts, including the way they have been criticized over time (see note 2)

Finally, it is important to state again that although most of the concepts discussed here were of biological forces, there are differences between these ideas. The same is true today, because the term "subtle force" or "subtle energy" is often used to refer to different hypothetical processes, and also used as metaphorical, descriptive, and explanatory labels. There is indeed much to clarify both from our past and present literature.

Notes

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