Chapter VII: The Researches of Professor Thury

The insufficient explanations of Chevreul and of Faraday, the scientific negations of Babinet, the conscientious experiments of the Count de Gasparin had led several scientists to study the question from the purely scientific point of view. Among them was a highly-gifted savant whom I visited at Geneva,--M. Marc Thury, professor of natural history and of astronomy in the Academy of that city. We are indebted to him for a remarkable and little known monograph,[56] which it is my duty to condense for this volume.

When we were in the presence of new phenomena (writes Thury) there was
only one alternative:

First, either to reject, in the name of common sense and of the
results acquired by science, all the pretended phenomena of tables as
so many childish sports unworthy of taking up the time of the true
scientist or scholar, since, on the very face of it, their absurdity
is evident; in short, to let the matter drop by refusing to give it
serious attention.

Or, second, to make a determined examination of it at whatever cost,
to study the fact in its details in order to lay fully open all the
sources of illusion by which the public is duped, separate the true
from the false, and throw a strong light on all aspects of the
phenomenon, physical, physiological, and psychological, in order that
the matter may be so superabundantly clear and evident that no further
excuse for doubt may remain.

Superfluous to say, the last method is the one adopted by Thury (as it was by Gasparin). He considers it to be the only suitable, efficient, and legitimate method.

Darkness saps the strength of science. Its strongest hold lies in bringing everything out into the full light of day. Here, then, lies the question: In these curious phenomena of the tables, is the explanation so clear that you can lay a finger on the causes of illusion and clearly show that there is in them no new and unknown element at work?

I do not think (replies the Genevan professor) that we have attained
to that degree of evidence. I wish only one proof, the explanation of
what has already been attempted.

If, then, it is well established that the common explanation is not
self-evident, in the eyes of all intelligent and sensible men, there
remains a task to do, a duty owed to science,--that of throwing full
light upon the phenomenon in question; and this task cannot be
exchanged for the easier one of treating with irony or disdain those
who have gone astray in the path that Science refused to illuminate.

The savants are, however, excusable for not going too quick (let us admit with Thury).

What! a perturbative force lurking, by the hypothesis, in the human organism sufficiently powerful to lift tables, and which yet had never produced the slightest derangement in the thousands of experiments that physicists are daily making in their laboratories! Their balances, responsive to the weight of a tenth of a milligram, their pendulums whose oscillations take place with mathematical regularity, had never felt the slightest disturbing effect of these forces, whose source is there present wherever there is a man and a volition! Now, it is the ardent wish of the physicist that the experiment shall always exactly tally the forecasts of theory. Must he then admit an unknown disturbing force?

And, even without going outside of the limits of the human organism, think, if the organism is unable to move the smallest part of itself when the part is deprived of muscles and nerves, or, when a single hair of our head is absolutely withdrawn from the influence of the will--think, I say, how much less (and with how much stronger reason) that nervous organism of ours would seem to be able to move inert bodies residing outside the limits of our own frames!

But, if there is a profound improbability in the thing, still, we cannot say that it is impossible. No one can show _a priori_ the impossibility of the phenomena described, as they demonstrate the impossibility of perpetual motion or the squaring of the circle. Consequently, no one has the right to treat as absurd the evidences which tend to confirm the experiments. Provided these evidences are furnished by judicious and truthful men, then they are worth the trouble of examination. If this logical course had been followed--the only true and equitable one,--the work would now have been done, and the learned men would have the glory thereof.

Thury begins by examining the experiments of Count de Gasparin at Valleyres.

The experiments of Valleyres (he writes) tend to establish the two
following principles:

1. The will, in a certain condition of the human organism, can act,
from a distance, upon inert bodies, and by an agency different from
that of muscular action.

2. Under the same conditions, thought can be communicated directly,
though unconsciously, from one individual to another.

As long as we were ignorant of any other facts than those resulting
from a movement effected by contact with the fingers of the hand, in a
way in which the mechanical action of the fingers became possible, the
results of the experiments upon the table were always of difficult and
doubtful interpretation. These results had to be necessarily based
upon an estimate of the mechanical force exerted by the hands
compared with the strength of the resistance to be overcome. But the
mechanical force of the hands is difficult to measure exactly, under
the conditions necessary to produce the phenomena.

Yet over and above that plan of work there remained two methods, of
operation to employ.

_a._ So to dispose the apparatus employed that the movement to be
produced shall be one that the mechanical action of the fingers could
not compass.

_b._ To set up movements at a distance without any kind of contact.

The following were our first experiments:

A. _Mechanical action rendered impossible._ The first experiment
attempted along this line gave wholly negative results. We suspended a
table by a cord that passed over two pulleys fixed in the ceiling and
had a counter-weight attached to the free end. It was easy, by
regulating this counterpoise, to balance in the air either the total
weight of the table or only a fraction, more or less great, thereof.

As a matter of fact, the table hung almost in equilibrium with the
weight, one only of its three legs touching the floor. The operators
placed their hands upon the top surface. We acted at first in a
circular direction, a disposition of the force the efficacy of which
had been established by previous experiments. We then tried in vain to
lift the table by detaching it from the floor. No positive result was
obtained.

We had already (during the previous year) had a table suspended to a
dynamometer, and the efforts of four mesmerizers were powerless to
relieve the dynamometer of an appreciable fraction of the weight of
the table.

But the conditions necessary for the production of the phenomena were
still unknown to us, and, consequently, when the experiments tried led
to negative results, we had to try others, without pressing too
hastily for inferences and conclusions. It was thus that we secured
the results which I am going to describe.

_Experiment with the Swinging Table._--We needed a piece of apparatus
of such a kind that the mechanical action of the fingers would be
rendered impossible. For this purpose we had a table made with a top
about 33 inches in diameter, and a central trifurcated leg
underneath. This table bore a close resemblance to the one which had
served our purposes up to that time, and could turn like its
predecessor. Still, the new table was capable of being transformed in
a moment into a mechanism such as I shall now describe.

The summit of the tripod becomes the fulcrum of a lever of the first
order which is able to balance freely in a vertical plane. This lever,
whose two arms are equal to each other and to the radius of the table
bears at one of its extremities the table-top, held by the edge, and,
toward the other extremity, a counterpoise which just balances the
weight of the table, but which can be modified at will. To the under
side of the table-top is fastened a leg resting on the floor.

After the necessary preliminary rotations, the table is harnessed up
in its second form. Equilibrium is first secured, then 3-5 of a pound
is taken from the counterpoise. The force required to lift the top by
its centre is then 4 ounces, and previous experiments have proved that
the adherence of the fingers of the operators (the top was polished,
and not varnished), together with the possible effects of elasticity,
form a total lower than that figure. Yet the top is lifted by the
action of the fingers placed lightly on its upper surface, at a
certain distance from the edge. Then the counterpoise is diminished;
the mechanical difficulty of lifting is augmented, yet still it takes
place. The weight is again diminished, and more and more, up to the
limit of the apparatus. The force necessary to lift the top is then 8
1-5 pounds, and the counterpoise has been relieved of 24 pounds; yet
the levitation is easily accomplished. The number of the operators is
gradually lessened from eleven to six. The difficulty goes on
increasing, yet six operators still suffice; but five are not enough.
Six operators lift 9 1-3 pounds,--an average for each man of about
1-1/2 pounds.

We now possess, in the apparatus just described, a gauge or instrument
of measurement.

B. The following movements were produced without contact:

The table on which were made the trials I witnessed has a diameter of
32 inches and weighs 31 pounds. An average tangential force of 4 2-5
pounds, which may be raised to 6 3-5 pounds, according to the greater
or less inequalities of the floor, applied to the edge of the table,
is necessary to give to it a movement of rotation. Ten is usually the
number of persons who operate about this table.

In order to assure ourselves of the absence of all contact, we placed
our eye on a level with the table in such a way as to see light
between our fingers and the surface of the table, the fingers
themselves remaining a little less than an inch above the top.
Usually, two persons would be observing at once. For instance, M.
Edmond Boissier was observing the legs of the table, while I was
watching the top. Then we exchanged roles. Sometimes two persons took
places at the extremities of one and the same diameter, the one
opposite the other, for the purpose of watching the top of the table.
Several times we saw it move, although we could not detect the
slightest touch by the fingers. According to my calculations, it would
require the contact of at least 100 fingers, or the light pressure of
thirty, acting voluntarily and fraudulently, to explain in terms of
mechanics the movements we observed.

Much more frequently still we obtained balancings without contact,
balancings which sometimes went so far as to tip the table entirely
over. To explain in terms of mechanical movement the effects we
observed, we should have to admit the involuntary contact of 84
fingers, or the light pressure of 25, or two hands acting with intent
to deceive. But these suppositions, also, are not at all admissible.

Nevertheless, we always felt that someone might present the objection
that it was difficult to observe these operations with precision, and
we were constantly urging M. Gasparin to convince the doubters and
sceptics in the matter of the non-contact of the fingers by means of
some mechanical device. Out of this arose the last experiment made at
that time, and the most conclusive of all. A light film of flour was
almost instantaneously spread over the table by means of a sulphur
bellows such as is used in vineyards. The movement of the chain of
hands above the table set it whirling. Then the film of flour was
examined and found to be inviolate from the touch of hands. Several
repetitions on different days always gave the same results.

Such are the principal facts which establish the reality of the phenomenon. Thury next takes up the more difficult investigation of courses.

_The Seat of the Force._--It is possible that the force which produces
the phenomena is a general telluric force which is merely transmitted
by the operators or set in action by them; or, possibly, the force
resides in the operators themselves.

To decide this question, we had a large movable platform constructed
which revolved on a perfectly vertical axis. Near the outer periphery
of the platform stood four chairs, and there was a table at the
centre. Four operators, experts in nervo-magnetic action, took their
places on the chairs, and, placing their hands on the table in the
centre, tried to give it circular movement by non-mechanical power. In
fact, the table soon began to move. Then it was stopped and fastened
to the platform by means of three screws. The effort exerted upon this
table by the four magnetizers was such that, at the end of
three-quarters of an hour of experimentation, the central supporting
leg, was broken. Yet the movable platform did not turn. The tangential
force required to mechanically move the empty platform was only a few
grams; loaded with the four operators, 250 grams was necessary,
applied about 28 inches from the centre. This figure would have been
much less if it had been possible to distribute the weight of the
operators uniformly.

The result of this experiment (of June 4, 1853) showed that the force
which tends to make the table turn is in the individuals and not in
the ground. For the force exerted upon the table tends to draw along
the platform with it. If, then, the platform remains motionless, it
must be that an equal and contrary force is exerted by the operators.
It is therefore in them that the base of the seat of the force
resides. If, on the contrary, this force had emanated, wholly or in
large part, from the ground, if it had been a force directly telluric,
the platform would have turned, the effort which the table exerted
upon it being no longer counterbalanced by an equal reaction
proceeding from the individuals.

_Conditions of the Production and Action of the Force._--I have said
that the conditions for the production of the force are little known.
In the absence of precise laws, I shall present what has been verified
in a greater or less degree in the case of the three following points:

_a._ Conditions of action relative to the operators.

_b._ Conditions relative to the objects to be moved.

_c._ Conditions relative to the mode of action of the operators upon
the objects to be moved.

THE WILL. The first and the most indispensable condition, according to
M. Gasparin, is the will of the operator. "Without the will," he says,
"we obtain nothing; we might sit there in chain twenty-four hours in
succession without getting the slightest movement." Farther on, the
author speaks, it is true, of unexpected movements different from
those which the will prescribes; but it is evident that he is
referring to a necessary combination of prescribed movements and
external resistances, the effective movements being the _resultant_ of
those that have been willed and of forces of resistance developed in
external objects. In short, the will is always the prime mover and
originator.

Nothing, it is true, in the experiments at Valleyres gave any
authority for believing that it could be otherwise than this. But it
is also certain that this purely negative result, or provisional
generalization, deduced from a limited number of experiments,--cannot
invalidate the results of experiments inconsistent with those, in case
such should exist. In other words, the will may ordinarily be
necessary, without always being so. Similarly, contact is ordinarily
necessary, and _always_ has been so with a large number of operators,
without, however, giving them the right to conclude that contact is
the indispensable condition of the phenomenon, and that the different
results obtained at Valleyres were only illusions or error.

Since we are dealing here with a point of capital importance, I shall
take the liberty of stating with some detail circumstances which seem
opposed to the thesis maintained by M. Gasparin. These facts, or data,
have as guarantee the testimony of a man whom I should like to be able
to name, because his scientific culture and his character are known of
all men. It was in his house and under his eyes that the events took
place which I am going to relate.

At the time when everyone was amusing himself with making tables turn
and speak, or in directing the motions of lead-pencils, fixed in
movable sockets, over sheets of paper, the children of the house
amused themselves several times with this sport. At first, the
responses obtained were such that you could see in them a reflex of
the unconscious thought of the operators, a "dream of waking
performers." Soon, however, the character of the replies seemed to
change. It seemed as if what they revealed could hardly have emanated
from the mind of the young interrogators. Finally, there was such an
opposition to the commands given that M. N., uncertain as to the true
nature of these manifestations in which a will different from the
human will _seemed_ to appear, forbade their being called forth again.
From that time forth, sockets and table rested undisturbed.

A week had scarcely rolled by, after the events just narrated, when a
child of the family, he who had formerly succeeded best in the table
experiments, became the actor, or the instrument, in strange
phenomena. The boy was receiving a piano-lesson, when a low noise
sounded in the instrument, and it was shaken and displaced in such a
way that pupil and teacher closed it in haste and left the room. On
the next day, M. N., who had been informed of what had happened, was
present at the lesson, given at the same time,--namely, when the dusk
was coming on. At the end of five or ten minutes he heard a noise in
the piano difficult to define, but which was certainly the kind of
sound one would expect a musical instrument to produce. There was
something about it musical and metallic. Soon after, the two front
legs of the piano (which weighed over six hundred and sixty pounds)
were lifted up a little from the floor. M. N. went to one end of the
instrument and tried to lift it. At one time it had its ordinary
weight, which was more than the strength of M. N. could manage; at
another, it seemed as if it had no longer any weight at all, and
opposed not the least resistance to his efforts. Since the interior
noises were becoming more and more violent, the lesson was brought to
a close, for fear the instrument might suffer some damage. The lesson
was changed to the morning and given in another room situated on the
ground floor. The same phenomena took place, and the piano, which was
lighter than the one up-stairs, was lifted up much more; that is to
say, to a height of several inches. M. N. and a young man nineteen
years old tried leaning with all their might on the corners of the
piano which were rising. Then one of two things happened: either their
resistance was in vain, and the piano continued to rise, or else the
music-stool on which the child sat moved rapidly back as if pushed or
jerked.

If occurrences like that had only taken place once we might think that
the child or the persons present were laboring under some illusion.
But they were repeated a great number of times, for a fortnight, in
the presence of different witnesses. Then, one day, a violent
manifestation took place, and thenceforth no unusual event occurred in
the house. At first, it was in the morning and in the evening that
these perturbations manifested themselves; then, invariably at any and
all hours, they occurred every time the child took his seat at the
piano, after five or ten minutes of playing. The phenomena happened
only with this boy, although there were others present (musicians);
and it made no difference which of the pianos in the house he used.

I saw these instruments. The smaller, on the ground floor, is a
rectangular horizontal piano. According to my calculations, a force of
about 165 pounds applied to the edge of the case, beneath the
key-board, is necessary to lift this piano as it was lifted by the
unknown force. The instrument in the first story of the house is a
heavy Erard piano, weighing, with the packing-box in which it was
sent, 812 pounds, as stated in the way-bill, which I myself saw.
According to my approximate calculations a pressure of 440 pounds is
required to lift this piano, under the same conditions as the first
was lifted.

I do not think that anyone will be tempted to attribute to the direct
muscular effort of a child eleven years old the lifting up a weight of
440 pounds.[57] A lady who had attributed the effect produced to the
action of the knees passed her own hand between the edge of the piano
and the knees of the child, and was thus able to convince herself that
her explanation had no foundation in fact. Even when the child got
upon his knees upon the piano-stool to play, he did not find that the
perturbations he dreaded ceased any the more.

These authenticated facts of Professor Thury are at once precise and formidable. What! two pianos rise from the floor and jump about! What do the physicists, the chemists, the learned pedants in office need, then, to arouse them from their torpor and make them shake their ears and open their eyes? What shall be done to remove their noble and pharisaical indolence?

But, happen what may, no one is occupying himself with the fascinating problem as stated, except scattered investigators who are freed from the fear of ridicule and are aware of the exact value of the human race, in large and small, and the worth of its judgments.

M. Thury next discusses the explanation based on "the will."

Did this boy (he says) _will_ what took place, as the theory of M. de
Gasparin would require us to admit? According to the boy's testimony,
which we believe to be wholly true, he did not will it; he seemed to
be visibly annoyed by what occurred; it disturbed his custom of
industriously practicing his lesson and offended his taste for
regularity and order, a thing well known to his intimates. My personal
conviction is that we positively cannot admit, in the case of this
lad, a conscious will, a settled design, to produce these strange
occurrences. But it is known that sometimes we have a double
personality, and one of them converses with the other (as in dreams);
that our nature then unconsciously desires what it does not will, and
that between will and desire there is only a difference in degree
rather than in kind. It would be necessary to have recourse to
explanations of this kind,--too subtle, perhaps,--in order to square
these piano-facts with the theory of M. Gasparin; and it would still
be necessary to modify and enlarge the facts if you admit that _even
unconscious desire_ suffices, in the absence of the expressed will.
There is, then, reason for doubt on this essential point. That is the
sole deduction that I wish to draw from the events I have related.

This levitation, equivalent to an effort exerted of 440 pounds, has its scientific value. But how could the will, conscious or unconscious, lift a piece of furniture of that weight? By an unknown force which we are obliged to recognize.

_Preliminary Action._--Power is developed by action. The rotations
prepare for the tippings and the levitations. The rotations and the
tippings, with contact, seem to develop the force necessary to produce
the rotations and tippings without contact. In their turn, the
rotations and the tippings without contact prepare for the production
of true levitations, such as those of the swinging table; and the
persons who have this latent force awaked in them are better fitted to
appeal to it a second time.

There is, then, a gradual preparation required, at least for the
majority of operators. Does this preparation consist in a modification
that takes place in the operator, or in the inert body on which he
acts, or in both? In order to resolve this problem, experimenters who
had been practicing at one table went over to another, operating on
which they found their full power unabated. The preparation therefore
consists in a modification that takes place in the individuals, and
not in the inert body.[58] This modification occurring in individuals
is dissipated rather rapidly, especially when the chain of
experimenters is broken.

_Inner Development of the Operators._--It is only after a certain
period of waiting that the operators, who have not so far acted, cause
even the easiest movement,--that of rotation with contact. It is
during this time that the force, or the conditions determining the
manifestation of the force, develop themselves. From that time on, the
developed force has nothing to do but to increase. That which takes
place, therefore, in this time of waiting, is a very important thing
to be considered. We already know that it is the operators themselves
who are modified. But what is it that takes place within them?

It must be that a kind of activity is set up in the organism, an
activity which ordinarily requires the intervention of the will. This
activity, this work, is accompanied by a certain fatigue. The action
is not aroused in all operators with equal ease and promptness. There
are even persons (the author estimates their number at one in ten) in
whom it appears that it cannot be produced at all.

In the midst of this great diversity of natural aptitudes, it is
observed that children "can secure obedience from the table just like
grown folks." Nevertheless, children do not magnetize. Thus, although
several facts seem to show that magnetizers (or mesmerizers) have
frequently a strong power over the tables, yet one cannot admit the
identity of magnetic power and power over the tables; the one is not
the measure of the other. Only, the magnetic power would constitute
(or presume) a favorable subjective condition.

A will simple and strong, animation, high spirits, the concentration
of the thought upon the work to do, good bodily health, perhaps the
very physical act of turning around the table, and, finally,
everything that can contribute to unity of will-power among the
experimenters,--all these things help to make efficacious the commands
addressed to the table with force and authority.

The tables (says M. de Gasparin) "wish to be handled gaily, freely,
with animation and confidence; they must be humored at the start with
amusing and easy exercises." The first condition necessary for success
with the table is good health and the second, confidence.

Among unfavorable circumstances, on the other hand, must be reckoned a
state of nervous tension; fatigue; a too passionate interest; a mind
anxious, preoccupied or distracted.

The tables--M. de Gasparin further says, in his metaphorical
language--"detest folks who quarrel, either as their opponents or as
their friends." "As soon as I took too deep an interest, I ceased to
command obedience." "If it happened that I desired success too
ardently, and showed impatience at delay, I no longer had any power of
action on the table." "If the tables encounter preoccupied minds or
nervous excitement, they go into a sulking mood." "If you are touchy,
over-anxious ... you can't do anything of any value." "In the midst of
distractions, chatterings, pleasantries, the operators infallibly lose
all their power." Away with salon experiments!

Must one have faith? It is not necessary; but confidence in the result
predisposes to a larger endowment of power in the seance of the
occasion. It does not suffice to have faith there are persons who have
faith and good will, yet with whom power of action is altogether
wanting.

Muscular force or nervous susceptibility do not seem to play any role.

Meteorological conditions have seemed to exercise some influence,
probably by acting upon the physique and the spirits of the operators.
Thus fine weather, dry and warm weather (but not a suffocating heat)
act favorably.

The especially efficacious influence of dry heat upon the surface of
the table[59] will perhaps receive a different explanation.

_Unconscious Muscular Action, produced during an especially Nervous
Condition._--So long as only movements with contact were known, in
which the movement observed was one of those which muscular action
might produce, explanations based on the hypothesis of unconscious
muscular action were certainly sufficient and much more probable than
all the other explanations which had been up to that time proposed.

From this point of view (entirely physiological) it is settled that we
must distinguish between the effort which a muscle exerts and the
consciousness we have of this effort. It will be remembered that there
exist in the human organism a great number of muscles that habitually
exert considerable effort without our being in the slightest degree
aware of it. It has been pointed out that muscles exist whose
contractions are perceptible by us in a certain state of the system
and unperceived in another state. It is therefore conceivable that the
muscles of our limbs might as an exceptional thing, exhibit the same
phenomenon. The preparation for the movement of the table, the special
kind of reaction that takes place at this interval of waiting, put the
nervous system into a particular condition in which certain muscular
movements may take place in an unconscious manner.

But, evidently, this theory is not sufficient to account for movements
without contact, nor those that take place in such a way that muscular
action could not produce them. It is therefore these two classes of
movements which must serve as the basis of new experiments and as the
foundation of a new theory.

How also explain the very peculiar and truly inconceivable character
of the movements of the table?--this starting to move, so insensible,
so gentle, so different from the abruptness characteristic of the
impetus given by mechanical force; these levitations so spontaneous,
so energetic, which leap up to meet the hands; these dances and
imitations of music which you would in vain attempt to equal by means
of the combined and voluntary action of the operators; these little
raps succeeding the loud ones, when the command is given, the
exquisite delicacy of which nothing can express. Several times when
someone asked a so-called spirit his age, one of the legs of the
centre-table lifted up and rapped 1, 2, 3, etc. Then the movement was
accelerated. Finally, the three legs beat a kind of drum-roll so rapid
that it was impossible to count, and which the most skilful could
never succeed in imitating. On another occasion, under the contact of
hands, the table was turning upon three legs, upon two, upon a single
one; and, in this last position, changed feet, throwing its weight
first upon one and then upon another with great ease, and with nothing
abrupt or jerky in its motions. Neither the experimenters nor their
most eminent opponents would ever be able to imitate mechanically this
dance of the table, and, above all, the whirling pirouettes and
changes of feet.

_Electricity._--Many have tried to explain the movements of tables by
electricity. Even supposing that they involve the very abundant
production of this agent, no known effect of electricity would account
for the movement of the tables. But, in fact, it is easy to show that
there is no electricity produced; for, when a galvanometer was
interposed in the chain, no deviation of the needle took place. The
electrometer remains as indifferent to the solicitations of the tables
as does the mariner's compass.

_Nervo-magnetism._--There is certainly some analogy between several
phenomena of nervo-magnetism and those of the tables. Those passes
which seem to favor balancing without contact; the motion imparted by
the chain to this man whom they cause to turn about (unless, indeed,
there is in this some effect of the imagination); finally, the power
that many mesmerizers exert over the tables--all this seems to
indicate a kinship between the two orders of phenomena. But, since the
laws of nervo-magnetism are little known, there is no conclusion to be
drawn from this, and it seems to me preferable, for the present, to
study separately the phenomena of tables, which are better adapted to
the experiments of the physicist, and which, well studied, will render
more service to nervo-magnetism than it could receive in a long time
from this obscure branch of physiology.

Thury next touches upon M. de Gasparin's theory of fluidic action. Being certain that he accurately understands this theory, he gives a resume of it in the following items:

1. A fluid is produced by the brain, and flows along the nerves.

2. This fluid can go beyond the limits of the body; it can be
_emitted_.

3. Under the influence of the will, it can move hither and thither.

4. This fluid acts upon inert bodies; yet it shuns contact with
certain substances, such as glass.

5. It lifts the parts toward which it moves, or in which it
accumulates.

6. It further acts upon inert bodies by attraction or by repulsion,
with a tendency to either join or separate the inert body and the
organism.

7. It can also determine interior movements in matter, and give rise
to noises.

8. This fluid is especially produced and developed by turning, and by
the will, and by the joining of hands in a certain manner.

9. It is communicated from one person to another by vicinage or by
contact. Yet certain persons impede its communication.

10. We have no knowledge of special movements of the fluid, which are
determined by the will.

11. This fluid is probably identical with the nervous fluid and with
the nervo-magnetic fluid.

_Application._--Rotation is a resultant of the action of the fluid and
of the resistances of the wood.

Tipping results from the accumulation of the fluid in the leg of the
table which is lifted.

The glass placed in the middle of the table stops the movement because
it drives away the fluid.

The glass placed on one side of the table makes the opposite side rise
because the fluid, fleeing from the glass, accumulates there.

Thury does not attempt the discussion of this theory. But we may repeat with Gasparin, "When you shall have explained to me how I lift my hand, I will explain to you how I cause the leg of the table to rise."

The whole problem lies in that,--the action of mind on matter. We must not dream that we can give a final solution of it at the present time. To reduce the new facts to conformity with the old ones; that is to say, to relate the action of mind upon inert bodies outside of us to the action of mind upon the matter in our bodies--such is the only problem which the science of to-day can reasonably propose to itself. Thury states it in general terms as follows:

_General Question of the Action of Mind upon Matter._--We shall seek
to formulate the results of experiment up to the point where
experiment abandons us. From there on we shall study all the
alternatives offered to our mind, as simple possibilities, some of
which will give place to hypotheses explanatory of the new phenomena.

_First principle: In the ordinary state of the body, the will acts
directly only in the sphere of the organism._--Matter belonging to the
external world is modified _on contact with the organism_, and the
modifications which it undergoes gradually produce others by
contiguity. It is thus that we can act upon objects at a distance from
us. Our action at a distance upon all that surrounds us is _mediate_
and not immediate. We believe that this is true of the action of all
physical forces, such as gravity, heat, electricity. Their effect is
gradually communicated, and thus alone they put distance behind them
and come into relation with man as a sentient being.

_Second principle: In the organism itself there is a series of mediate
acts._--Thus the will does not act directly upon the bones which
receive the movement of the muscles; nor does the will modify any more
directly the muscles, since, when deprived of nerves, they are
incapable of movement. Does the will act directly upon the nerves? It
is a mooted question whether it modifies them directly or indirectly.
Thus the substance upon which the soul immediately acts is still
undetermined. The substance may be solid, may be fluid; it may be a
substance still unknown, or perhaps a particular state of known
substances. In order to avoid a circumlocution, let me give it a name.
I shall call it the _psychode_ ([Greek: psyche], soul, and [Greek:
odos], way).

_Third principle: The substance upon which the mind immediately
acts--the psychode--is only susceptible of very simple modifications
under the influence of the mind_, for, since the movements are to be
somewhat varied, an extensive and complicated apparatus appears in the
organism,--a whole system of muscles, vessels, nerves, etc., which are
wanting in the inferior animals (among whom movements are very
simple), and which would have been unnecessary had matter been
directly susceptible of modifications equally varied under the
influence of mind. When movements are intended to be very simple (as
in the case of infusoria) the complicated apparatus is wanting and the
life-spirit acts upon matter that is almost homogeneous.

The following four hypotheses regarding the psychode may be formed:

_a._ The psychode is a substance peculiar to the organism, and not
capable of emerging from it. It acts only mediately upon everything
outside of the visible organism.

_b._ The psychode is a substance peculiar to the organism, capable of
extending beyond the limits of the visible organism under certain
special conditions. The modifications it receives necessarily act upon
other inert bodies. The will acts upon the psychode, and thus
mediately, upon the bodies that the sphere of this substance embraces.

_c._ The psychode is a universal substance which is conditioned in its
action on other inert bodies by the structure of living organisms, or
by a certain state of inorganic bodies--a state determined by the
influence of living organisms in certain special conditions.

_d._ The psychode is a peculiar state of matter, a state habitually
produced within the sphere of the organism, but which may also be
produced beyond its limits under the influence of a certain state of
the organism,--an influence comparable to that of magnets in the
phenomena of diamagnetism.

Thury proposes the adjective _ecteneic_ (from [Greek: ekteneia], extension) to describe that special state of the organism in which the mind can, in some measure, extend the habitual limits of its action, and he styles "ecteneic force" that which is developed in this state.

The first hypothesis (he adds) would not be at all adapted to explain
the phenomena with which we are concerned. But the three others give
rise to three different explanations, in which (he assures us) the
greater part of the phenomena investigated will be comprised.

_Explanations based upon the Intervention of Spirits._--M. de Gasparin
has shown the error of all these explanations:

1. By theological considerations.

2. By the very just remark that we should not resort to explanations
which introduce spirits into the problem until other interpretations
have been proved to be entirely insufficient.

3. Finally, by physical considerations.

Looking at the question here solely from the general physical point of
view, I do not follow M. de Gasparin (says Thury) in his exploitation
of theological explanations. As to the second, I will only call
attention to the suggestion that the sufficiency of explanations
purely physical should strictly apply only to the Valleyres
experiments, where, in truth, nothing gives evidence of the
intervention of wills other than the human will.

The question of the intervention of spirits might be decided from the
tenor or content of the revelations, in any case in which this content
would be such as evidently could not have originated in the human
mind. It is not my intention to discuss this point. The present study
takes cognizance solely of movements of inert bodies, and we have only
to consider, among the arguments of M. de Gasparin, those which are
included in this field of view.

Now, his arguments on this point seem to me to be all summed up in
these slightly ironical lines: "Strange spirits! ... whose presence or
absence could depend upon a rotation, depend upon cold or warmth, or
health or disease, on high spirits or lassitude, on an unskilful
company of unconscious magicians! I have the headache or the grip,
therefore the daemonic beings will not be able to appear to-day."

M. de Mirville, who believes in spirits who manifest themselves
through the agency of the fluid, might reply to Gasparin that the
conditions of the ostensible manifestation of spirits are perhaps the
fluidic state itself; that if this is so, we might very well, in a
seance phenomenon, have a fluidic manifestation without the
intervention of spirits, but not the intervention of spirits without a
preliminary fluidic manifestation, and that, thus, anyone will invite
such manifestation only at his own risk and peril.

Thury next discusses how the question of spirits ought to be considered.

The task of science (he writes) is to bear witness to the truth. It
cannot do so if it borrows a part of its data from revelation or from
tradition; to do this would be a begging of the question, and the
testimony of science would become worthless.

The facts of the natural order are connected with two categories of
forces, the one that of _necessity_, the other that of _freedom_. To
the first belong the general forces of gravitation, heat, light,
electricity, and the vegetative force. It is possible that we may
discover others some day; but at present they are the only ones we
know. To the second category belong solely the mind of animals and
that of man. These are truly _forces_, since they are the cause of
_movements_ and of various phenomena in the physical world.

Experience instructs us that these mental forces manifest themselves
by the intermediary of special organisms, very complex in the case of
man and the superior animals, but simple in that of the lowest, among
which latter class mind has no need of muscles and nerves in order to
manifest itself externally, but seems to act directly upon a
homogeneous matter, the movements of which it determines (the amoeba
of Ehrenberg). It is in these elementary organizations that the
problem of the action of mind on matter is stated, after a fashion, in
its simplest terms.

When once we have admitted the existence of the will as distinct, at
least in principle, from the material body, it becomes solely a
question of experience to ascertain whether other wills than that of
man and the animals play any role whatever, frequent or occasional, on
the stage of life. If these wills exist, they will have some means or
other of manifestation, with which _experience alone_ can make us
acquainted. As a matter of fact, all that it is possible to affirm, _a
priori_, is that, in order to appear, they _must_ manifest themselves
through some one of the forms of the eternal substance we call matter.
But, to say that this matter must necessarily have an organization of
muscles, nerves, etc., would be to hold to a very narrow idea, and one
already belied by observation of the animal kingdom in its lower
types. As long as we do not know what the bond is that unites the mind
to the matter in which it manifests itself, it would be perfectly
illogical to lay down, _a priori_, particular conditions which matter
must observe in this manifestation. These conditions are at present
wholly undetermined. Thus we are at liberty to seek for signs of these
manifestations in the cosmic ether or in ponderable matter; in the
gases, the liquids, or the solids; in unorganized matter, or
particularly in matter already organized, such as that of which man
and the animals are built up. It would be poor logic to affirm that
other wills than those of men and animals cannot be discovered, on the
ground that, heretofore, nothing of the kind has been seen; for facts
of this kind may have been observed, but not scientifically elucidated
and authenticated. Furthermore these wills might appear only at long
intervals, or what seem long to us; but the vast abysses of nature's
epochs are not to be spanned by our little memories or measured by the
momentary duration of our lives.

Such are the facts and the ideas set forth in this conscientious monograph of Professor Thury. It is easily seen that, in his opinion (1) the phenomena are positive facts; (2) that they are produced by an unknown substance, to which he gives the name _psychode_, a something that, by the hypothesis, exists in us and serves as the intermediary between the mind and the body, between the will and the organs, and can project itself beyond the limits of the body; (3) that the hypothesis of spirits is not absurd, and that there may exist in this world other wills than those of man and the animals, wills capable of acting on matter.

Professor Marc Thury died in 1905, having devoted his entire life to the study of the exact sciences. His specialty was astronomy.