SECOND TREATISE

CRYSTALS

Crystals: the relation of these and of the magnet to human organs. The poles of crystals. Light and force of these.

23. Previously to my visits, Miss Nowotny's physician had repeated some of the observations of the older physicians in cataleptic cases, in particular those which Dr. Petetin, at Lyons, in 1788, as well as other persons, had investigated and made known;—that when a powerful magnet was placed upon the hand, it adhered to it in the same way as a piece of iron to the magnet; moreover, that water through which the magnet had been passed a few times, was accurately distinguished by the patients from common water. The latter was first observed and made known by Mesmer, often enough ridiculed, and as often re-asserted. We shall see in the course of the present investigation how much of it is found true, and how much false, by the test of physics. The adhesion1 of a living member to a magnet is a fact totally unknown both in physics and physiology, and few persons have satisfied themselves on the point by inspection; it is necessary, therefore, to examine and elucidate it in some measure in this place. When the sick Miss Nowotny lay unconscious and motionless in a cataleptic condition, but free from spasms, and a horse-shoe magnet, capable of sustaining some 22 lbs., was brought near her hand, this adhered to it in such a manner that when the magnet was raised, or moved sideways, backward, or in any desired position, the hand remained constantly attached to it, as if it had been a piece of iron cleaving to it. The patient remained perfectly unconscious all the while; but the attraction was so strong, that when the magnet was drawn down in the direction of the feet, beyond the reach of the patient's arm, she not only did not leave it, but, in an unconscious state, rose up in the bed and followed the magnet with her hand as long as it was at all within her reach: thus it looked as if the patient had been grasped by the hand, and her body thus been drawn toward her feet. Finally, when the magnet was removed beyond its distance of attraction, she was indeed compelled to leave it, but then remained unalterable and immoveable in the position in which she had been placed, according to the well-known manner of cataleptic patients. This I saw daily, between six and eight o'clock in the evening, when the patient had her fits; and eight or ten persons, physicians, physicists, chemists, and friends of science, were usually witnesses of it, to name whom can be of no essential use to me.

When I visited the girl at other times of the day, in the morning for instance, I found that the phenomena were still the same at the time of her best and clearest consciousness. Her hand followed the magnet which I placed on it, exactly in the same way as when she was in the unconscious cataleptic condition. The account of the matter which I obtained from her added little to the explication of this physical singularity; she described her sensation as an irresistible attraction, which she felt compelled to follow unconditionally and involuntarily, and which she was obliged to obey even against her will. It was an agreeable sensation, as if connected with a cool gentle wind, issuing from the magnet on to the hand, which seemed to be attached to it as by a thousand fine threads, and to be drawn along by it. In other respects she knew of nothing at all like in life, and the whole was a peculiar, indescribable sensation, in which lay a refreshing, infinite pleasure, when the magnet was of the right size and not too strong.2

I subsequently had opportunity to observe exactly the same phenomenon in Miss Reichel. The complaint was different here, but also connected with periodical cataleptic fits, and both in these and in the awake condition her hand followed a strong magnet, exactly in the way I have described it in Miss Nowotny. Professor Lippich reported the same to me of a stage of the disease of Miss Sturmann, which I was prevented from examining myself; and I have every reason to place unconditional trust in the accuracy of the statement. These different cases, compared with those of a similar kind which Petetin, Rick, and others furnish from past times, leave no doubt of the correctness of the fact, that in certain diseases, especially those in which catalepsy exists, a distinct attraction occurs between the human hand and strong magnets.3

I also made an experiment on the feet of Miss Nowotny; there also I found a like attraction, but far weaker; but no other place, sensitive in this way, existed in any part of the body.

24. The first and most immediate question that arose now was, whether the attraction which the magnet exercised upon the patient was reciprocal, or whether it was exerted by it upon bodies capable of participating in the diffusion of magnetism, and, like iron, temporarily converted into magnets by the approximation of a magnetic body; in other words, whether, through her diseased condition, magnetism, and, with this, magnetic attraction, resided in herself? To decide this I took some iron filings and brought the patient's finger over them; they did not adhere in the slightest degree, even when she was in contact with the magnet, and might thus have been more strongly influenced than she might have been naturally. A suspended magnetic needle which I brought to her, and which I bade her hold her finger dose to at both poles, and in variously modified alternating ways, was not caused to diverge or oscillate in the least. Another experiment in reference to this point was made at the desire and in the presence of M. Baumgartner. When the baud, and with it. the whole arm, were lifted up by the magnet, it seemed to many that the horse-shoe became as much heavier as the weight of the attached burden, the arm, amounted to. I could not find this myself, but many persons believed that they felt it distinctly. The horse-shoe was therefore attached to the beam of a pair of scales, and its weight balanced by a counterpoise. After the patient's hand had been spread out flat, with the back on a firm support, I held it fast down upon this by the tips of the fingers, and the freely suspended magnet was brought near to it: the hand strove to move toward this, and I was obliged to exert some force to keep it back; but the index of the balance did not stir in the least, even when the magnet almost touched the fingers, and then strove so convulsively to contract, that I had much trouble to retain them in their flat position.

While I was busied with these investigations, the known statement of Thilorier, that he had magnetised steel by induction from nervous patients, appeared in the journals: whether the induction here depended solely or only in part upon the disease, I must leave unsettled: the result in Vienna was, that I soon received news from their physician that both Miss Reiehel and Miss Maix converted every steel needle into a magnet, by holding it in the hand for some time. I went to see the patients, who assured me of the correctness of the matter, and showed me knitting needles which supported common sewing needles. I made the experiment with them myself; procured knitting needles which were not at all magnetic, removed all magnets from the vicinity of the patients, and gave them the needles. At my desire they held them in the hand, first the same length of time, then twice as long as in the previous experiments, in which their medical attendant stated he had produced magnets with them, but the needles were not magnetic now, and all endeavour to make them so was in vain. Doubtless it had been neglected before to examine the condition of the needles previously to the experiment, for among a dozen knitting needles always half are more or less magnetic. Lastly, I was assured that Miss Sturmann was so magnetic that she caused the magnetic needle to diverge from 20 to 30 degrees. I was invited to a trial by Professor Lippich, and really saw a freely suspended needle considerably deflected. As the needle was not sufficiently secured from currents of air, I undertook the experiment next day, with the precaution of placing the needle in a vessel which was covered by a glass plate at the top, so that we could see all that took place. At the side I had made a round hole just large enough to admit a finger. By this means the patient could bring her finger quite close to the needle without setting the air in motion, while the breath of those standing round could no longer exert any influence on the experiment. When the finger was introduced, it appeared this time that some attraction occurred. I examined the tip of the finger, and as it seemed rather moist, I rubbed it over with flour for another trial: then all attraction for the magnet was at once at an end; the needle remained motionless. It was evident that in the former case the very mobile needle had adhered to the finger from the presence of slight perspiration, and when the slight stickiness of this was removed by the flour, all attraction ceased directly. It was not of magnetic nature, but an effect of adhesion. Quite superfluously I afterwards introduced Miss Sturmann's finger into the helix of a differential galvanometer: neither when inserted or taken out was any induced current perceptible, and the astatic needle remained immoveable.

25. From the preceding it follows, that the attraction exercised by the magnet upon the hands and feet of cataleptic patients is nothing ponderable; it has no supporting power, cannot even raise iron filings, and is equally incapable of affecting the magnetic needle and inducing a magnetic current. The arm lifted up in catalepsy therefore supported itself, and its passive attraction was quite different in its import from that of iron toward the magnet, or, more accurately, toward magnetically oppositely polarized matter in the sense hitherto received.

It is known well enough that we are not acquainted in physics with any attraction which is not reciprocal. On the other hand, it is equally well known that a person in a state of cataleptic unconsciousness, which cannot be feigned, not only has no free will, but in fact no will at all:4 since, therefore, the magnetic mechanical attraction by the magnet is a fact, which is not only established here by sufficient experiments, but may readily be tested and confirmed in every large town, where such patients are never wanting, it acquires, in spite of all its apparent strangeness, a solid, scientific certitude, and imperiously claims further investigation. Not in order to explain it, but to render it provisionally in some degree comprehensible, I venture to refer to all the attractions and repulsions which the vegetative life of animals and plants unceasingly brings to pass, in thousand-fold variety, without our being able at present either to perceive or even to infer a counter attraction. A root penetrates strongly into the hard soil, breaks and bursts powerful mechanical obstacles: we perceive no cause for the counter-attraction or counter-expulsion which so powerfully impels it thereto, and yet it happens. Similar conditions lead the hand of the patient toward the magnet, whether we now comprehend it or not.
26. When, instead of a middle-sized magnet of some 201b. capacity, we took a strong one capable of bearing 901b. and placed this on the flat hand of Miss Nowotny, she grasped, both in the conscious and unconscious state, the presented ends of the horse-shoe, and laid hold of it so firmly that it could not be taken away from her without great effort. She herself was unable to loosen her hold. The whole hand was clenched spasmodically, and the cramp knitted the fingers round the magnet, and contracted the whole hand so violently that all voluntary power of motion ceased. 5
27. I have already (§ 2) mentioned the magnetized water which the patient immediately distinguished from common water, when ignorant of what had been done to it. Nothing could be more disagreeable than the reappearance of an apparently so absurd thing, which all physicists and chemists are horrified even to hear of. But in spite of this, I could not refuse to admit what I saw before my eyes as often as I tried it; namely, that the girl always determined, and unfailingly distinguished, a magnetized glass of water from an unmagnetized. The force of facts cannot be combatted by any reasoning; I was compelled to recognise what I was by no means able to comprehend. But when I again met with the same subsequently in Misses Sturmann, Maur, Reichel, Atzmannsdorfer, and others, and saw it in a still stronger degree, I gave up all doubt and opposition to a phenomenon, the actuality of which no longer admitted of contradiction in any reasonable manner.6

But the Singularity seemed to reach the height of incomprehensibility when it proved that not merely the magnet, but even a simple glass of magnetised water, possessed the power of drawing along the hand of Miss Nowotny. It is true that this occurred in a much weaker degree, but her hand was unmistakeably attracted, both in the catalepsy and at every other time, by a magnetized glass of water, in such a manner that a tendency to follow this in every direction made itself evident.

Contemplating this, and convinced that so strange a phenomenon could not exist isolated in nature, I was desirous of trying whether the same effect as that of the water might not be brought about by means of some other body; if this proved to be so, I hoped to see cases occur with various modifications, from which some laws might be deduced. With this view, all sorts of minerals, preparations, drugs, and other things, were rubbed with the magnet, and the patient was tried with them in the same way as with the magnetized water; and it actually happened that all reacted at once upon her, more or less, in the same way as the magnetized water: they attracted the patient's hand more strongly or weakly, but in variously modified ways. Some produced spasms throughout the whole body, others only in the arms, others only in the hand, others scarcely caused any effect, although all had been equally strongly magnetized. It was evident, therefore, that some difference lay in the matter itself, and required to be taken into account here.

30. To investigate this, I now tried to bring the same substances into contact with the patient, Without having been previously magnetized, in their natural condition. To my great surprise, they also acted now upon the patient, with a force which very often yielded but little to that which they had exhibited in the magnetized condition. But the action was not always accompanied by a solicitation to follow the object; on the contrary, that other effect (§ 5) which had made the patient grasp the magnet convulsively in her hand, presented itself in various gradations of force. The method of experiment which I followed here, consisted in this: I first placed the various bodies in the patient's hand while in the cataleptic state, and observed the effect, then repeated the same when he was in a state of perfect consciousness, out of the catalepsy. By these comparisons, it was made evident that the action was qualitatively the same in both cases, but it showed itself incomparably stronger quantitatively in the catalepsy than out of it. The effect essentially consisted in this: that the various bodies, when placed in the hand of the unconscious patient, either—

1. Determined an actual tonic spasm in the fingers, as the magnet did, and compelled an involuntary clenching of the hand which held the bodies. These again could be divided into such as simultaneously solicited the hand to follow them, and such as no longer visibly produced this effect; or
2. Those which appeared inactive, and left the hand at rest; the former effect presented itself in various degrees of energy. It either ensued suddenly, directly the hand came in contact with the bodies, or it followed gradually, slowly, or rapidly. The fingers began to curl, by degrees were drawn more inward, after some time closed into a clenched hand, and then remained in a state of tonic cramp. This was precisely the effect produced by placing a very weakly magnetic rod in the patient's hand while in the unconscious state of catalepsy.

Comparing the applied bodies one with another, they arranged themselves in this respect, not according to the character of their substance, nor even in the electro-chemical series; in fact, the same chemical substances in specimens of different kinds sometimes produced the effect, sometimes did not: for example, calcareous spar, sugar, quartz, &c. First of all I perceived that there was not a single amorphous body among those which re-acted so as to make the hand close upon them; and, on the other side, that all 1 bodies which did so were crystallized. There were, nevertheless, a good many crystalline bodies without the power. When, now, excluding all amorphous substances, I arranged the whole of the crystalline bodies in two groups, opposing those which showed themselves powerless to those which exerted the magnet-like influence upon the hand, I found upon the former, the inefficient side, all the confusedly crystallized—such as loaf sugar, carrara marble, and dolomite; and further, the substances composed of many oppositely directed groups of crystals; such as prehnite, wavellite, lumps of sugar of lead, masses of Konigsberg crystallized silver; on the latter, the effective side, all simple, free crystals, and all those where the crystalline masses had parallel principal axes,—such as celestine, many specimens of gypsum, and fibrous red and brown ironstone. For the sake of distinct? ness, I give here a list of the bodies with which I made the experiments.

All these comparisons may be finally concentrated into the facts, that finely granular crystalline carbonate of lime, dense quartz, and loaf sugar, were inactive; but a free crystal of calcareous spar, a prism of rock crystal, or a good crystal of sugar-candy, therefore every perfectly free crystal, when placed in the patient's hand, irresistibly and arbitrarily excited the fingers, attracted them and drew them inward so as to grasp the crystal, and this in some of the cases with the most violent tonio spasms. Consequently, simple crystals here furnished a peculiar means of detecting a primary force, which had hitherto been altogether unknown. So far as is at present made out, this property does not belong to matter, as such, but to its form, and in fact to its condition of aggregation. Pouillet, in Miller's translation of his " Manual of Physics," p. 167, says expressly, that " it has never yet been observed in ponderable matter, that the form, the arrangement of the molecules, can be the cause of new forces acting at a distance." But this is exactly the case here; the matter must be crystallized, otherwise it does not re-act in this manner.8

32. When I now tested one of these bodies separately, I found that the capability of producing spasms of living organs did not reside in equal degree in all parts of its surface. Points were formed, and the patient readily detected those which possessed the power either very weakly or not at all; others, on the contrary, where it manifested itself in increased strength. It was discovered that every crystal presented especially two such points, in which the force peculiarly resided. And these points lay diametrically opposite to each other in every crystal; they were the poles of a primary axis of the crystal. Both acted in the same way, but one always much more strongly than the other, and with the distinction that from one appeared to issue a cool, from the other a softer, gently warm (seeming) current of air.

33. Endeavouring to trace the expressions of this force in various directions, I now made the experiment of drawing the stronger poly of a moderate sized crystal which I had at disposal, a rock-crystal two inches thick and eight inches long, a certain distance down along the inside of the hand, in the same way as is customary with the magnet, when it is intended to throw the patient into the usual sleep. It was found that the effect was exactly the same as that produced by a small magnetic needle, such- as is used in a compass, which I had at hand for comparison. This needle was nearly six inches long, one-eighth of an inch broad, and one twenty-fifth of an inch thick, weighed about one hundred and eighty-five grains, and supported about twice its own weight. When I drew the point of the crystal along downward from the wrist, slowly through the palm of the hand to the tips of the fingers, the patient had the sensation of a pleasant, light, cool breeze directed over her; when I took the little magnetic needle, it produced the same in the like degree. When I reversed the experiment, so that I carried the pass from the middle finger upwards to the wrist, the magnetic needle produced a contrary, luke-warm sensation, evidently disagreeable to the patient;—the point of the crystal produced exactly the same when the reverse pass was made with it in the same way. Another time I brought a crystal three times as large: when drawn downward over the hand, it behaved like a magnetic bar capable of supporting a pound and a quarter of iron; but the reversed pass, up the hand, acted so violently, that the spasmodic condition produced by it ascended along the arm as far as the arm-pit, continued for several minutes, and by its violence rendered a repetition improper.

34. Furnished with these facts, I repaired to the hospital of our University, with a view to try whether the observations which I had gathered from Miss Nowotny could be repeated on other 'similar patients, confirmed, and brought to some degree of generality. Under the kind permission of Dr. Lippich I again directed my attention to Miss Angelica Sturmann. I made the pass over her hand with the apex of a rock crystal six inches long and two inches thick.

The effect ensued immediately, the patient felt the warm and cool sensations very distinctly when the passes were made over the hand When I applied the other pole of the crystal in the same manner, the sensations were just of the same kind, but weaker and reversed: these two patients therefore agreed with each other. The action on the sick Miss Sturmann was so strong that it affected the whole arm as far as the shoulder, the warm and cold sensations being prolonged all the way up. When I subsequently applied a crystal three times as large, this acted so powerfully upon the hand, immediately upon the first pass, that her colour came and went suddenly, so that I did not venture upon a second experiment with it here.

I now tried the pass from the head down over the face; she described everything here exactly in the same way, and the sensation was especially perceived along the temples. Counter-experiments with the above-mentioned magnetic needle produced exactly similar effects, only the needle was here evidently felt more weakly than the rock crystal. Finally, I afterwards made the same experiments on Miss Maix. On this very sensitive patient, who, however, always remained fully conscious, the crystals acted not merely on the line of the pass, but over a broad strip up and down the hand, which action ascended all up the arm. Two months later, I tried Miss Reichel. This, to outward appearance, healthy and strong girl, possessed such sensibility to the crystal pole, that she perceived its approach even at considerable distances. Like her predecessors, she found the pass downward cool, upward warm, with the northward pole (—M); with the southward (4. M), on the contrary, t that downward warm, that upward cool. Lastly, I be- came acquainted with Miss Maria Atzmannsdorfer, and found in her a sensitive subject,9 who felt the pass of the crystals, strongest of all. Even little crystals of fluor spar, selenite, sulphuret of iron, an inch or so long, produced a sensation of ebld when passed down the hand: with rather thin acicular crystals, I could, so to speak, describe lines upon the hand; but the pass upward produced warmth of the hand, and so adversely upon her, that it affected her whole body unpleasantly, and began to produce spasms as soon as I repeated it.

35. As I was recounting all this to a friend, and, in order to show him distinctly how I had operated upon my patients, drew the same rock-crystals along over his hand, he looked at me with wondering eyes, and said that he himself felt the same that I had been describing to him of my patients, —the cool breeze, quite distinctly,—as often as I passed the point of the crystal over his hand. He was a strong healthy man, in the prime of life, who allowed me to name him openly, and to call upon him, as a witness,—Mr. Carl Schuh, a private gentleman residing here, well known for his great knowledge in natural sciences. After that, I made the experiment on all my own circle of acquaintance, and on many strangers, among whom were physicians, physicists, and chemists. I have permission to name especially among these, our renowned naturalist, Prof. Endlicher, chief of all the public botanical institutions. It appeared that not only my sick patients, but a great many other persons, shared these sensations, and that a large crystal of quartz, selenite, heavy spar, fluor-spar, and other substances, carried along sufficiently close over an open hand, produced, and rendered evident to the consciousness, in a tolerably large number of persons, certain peculiar sensations, which manifest themselves in the first place as heat and cold. This was equally the case when I previously heated the crystal to the temperature of the blood, to meet the objection, that the sensation might be accounted for by the radiation of heat from the hand to the stone. Many could tell me at once, with the face averted, whether I had made the pass over the hand with the positive or negative, i. e. with the weaker or stronger pole.

It results from all this, that the following laws exist in nature:—

• A peculiar, hitherto overlooked force, resides in matter which, when the latter has taken the form of a crystal, appears effectively in the direction of the axes.
• It manifests itself most strongly at the two poles, but differently, and in an opposite manner, at each.
• Its effect agrees perfectly with that of the magnet, and the magnetic poles, in every case, where it is directed upon sensitive human organs.

36. In order to put every one in a position to repeat the experiments on his own acquaintance, I observe expressly, that a large free crystal, with a natural point, is requisite; larger in proportion as the person is less sensitive. Heavy spar, fluor spar, and selenite, are especially well adapted. It makes no difference whether the skin is delicate or coarse; I have sometimes found the roughest mechanic's hand more sensitive than the softest skin of a professional person. The point of the crystal must be carried slowly, as closely as possible without actual contact, sweeping from the end of the arm over the inside of the expanded hand, through the palm, and over the middle finger as far as the tip, at such a rate that one pass occupies some five seconds. The crystal is to be held perpendicularly to the surface of the hand. Among my own acquaintance I have found more than half the persons sensitive. I never told them what I had in view; I asked for the hand, passed the crystal a few times over it, and then asked whether any effect was felt, and of what kind? The answer usually was, a cool or a warm breeze. It need scarcely be mentioned, that this sensation is very delicate and fine; for, if it affected the hand so strongly as not to require any particular attention, it would not have remained to be discovered, and brought forward now, but would have been long since generally known. Persons who do not feel it one day often feel it the next, or the day after, or a week later. I met with a remarkable instance in my own younger daughter, Ottone. She always felt a large selenite crystal very distinctly, while her brothers and sisters could scarcely feel anything. She suffered for some time from head-ache, which gradually increased; at last she was obliged to lie down. Two days after, she was seized for the first time in her life with violent spasms, lay sick a fortnight, and then recovered. Now, however, she scarcely felt the selenite crystal at all; the attack of illness had wholly removed the sensitiveness to it. Thus this sensitiveness varied even in the same persons at different times, and with their state of health. Very frequently the sensation did not become evident at the first, but at the second or third pass. Sometimes a person felt the first pass most strongly, the second and third were not perceived, while with the fourth and fifth the sensation again distinctly presented itself. It would not do to make the pass too rapidly; the full action requires some little time. It occurred, also, that it preceded the crystal, and was felt at the points of the fingers when the crystal had only reached the palm of the hand; on the contrary, it only manifested itself distinctly in other persons, after the crystal had completely passed off the hand. In some places the eyes of the persons have been bound, and then varying statements have been received. This cannot astonish, after what has just been said; the answers will always be the same from sensitive persons; from persons but slightly sensitive they will be the most uncertain: the binding of the eyes places people in an unnatural and inquiet condition, so that their attention is divided and distracted, and the requisite calm for such delicate observations is usually wanting. If many persons are present, saying and asking all kinds of things, walking to and fro, and the agitation and distraction are increased, it is natural that the answers to the questions should be incoherent concerning a sensation which does not sweep over the hand like a wire brush. To many persons the reversed pass, from the hand upward toward the arm, is more evident than the downward pass. But some persons are absolutely insensible; and these perhaps are the healthiest. The one, the northward pole,10 usually acts more strongly than the other, the southward pole: the slight warmth is generally less perceptible than the coolness. It almost always contributes to increase the distinctness and strength when the hand is extended in the direction of the meridian, with the fingers directed to the south. Unfortunately, no further contacts may be allowed to exist during this, because they injure the delicacy of sensation, and divert the attention, which must be wholly concentrated here. It is worthy of remark, that this, like every other sense, becomes improved by practice. A person who never drinks wine, coffee, or tea, can seldom distinguish the different kinds of them; while a practised drinker discovers the slightest difference at once and distinctly. Mr. Schuh prepared for me in a short time series of crystals completely agreeing with those which the sensitive patients had formed. The same was speedily effected by Mr. Studer, a young man from Zurich, staying here, and his series agreed almost perfectly with that of Mr. Schuh.

37. Up to this point it was made out that in crystals resides a force of a polar nature, which they possess in common with magnets. It was next to be inquired whether this was of the same kind, and perhaps only quantitatively different, or was qualitatively different from that which we have hitherto understood by the term magnetism. If the former, it must be capable of being reduced to the same laws. It should attract iron filings, like not only magnetic nickel (chromium, manganium, cobalt11), but also oxidised bodies, even impure ores like magnetic iron-stone. Moreover, it ought in like manner, in quartz, selenite, &c., as it does in steel, not only to influence organic living bodies, but also convert bodies capable of becoming magnetic, such as steel, iron, nickel (cobalt, &c.), into magnets, when applied to them in the same way. When I dipped the polar end of my crystal into fine iron filings I could not detect any attraction. In order to have at my disposal the crystalline force, in its greatest possible strength, I bought the largest crystal that 1 could obtain, a prism of rock crystal from Gotthard, of eight inches in diameter, a six-sided colossus, with pyramidal ends, which I had some difficulty in using, and the action of which on the hand of the most sensitive of my healthy friends, Mr. Schuh, was so strong that he described it as feeling as if cold air were gently blown upon him through a straw. I placed a fine sewing-needle before this powerful crystal, and rubbed this with it in the same way as we do with a magnetic bar when desiring to convert it into a magnet. I made a dozen passes over it, and tried it with iron filings; it did not attract any. I repeated the passes more than a hundred times: but still it did not lift even the most minute of the iron filings. As a counter-experiment, I made a single pass over the sewing needle with the small magnetic needle which Miss Sturmann had found weaker than the little rock crystal previously applied to her, and it at once took up a long beard of filings from them. Therefore the points of the crystals could not inoculate the needle by rubbing, with a force capable of acting on iron. However, were this the case, it was still possible to excite such on it, after the manner of magnetic distribution, under the immediate influence of a crystal pole, and to render it capable of attracting iron filings in the same way that an iron rod is made to do so, by placing the pole of a magnet upon it. To try this, I attached a fine steel needle to the points of various large crystals, and dipped it, in this connexion, into filings. It did not lake up the least trace of them.

When I approached the polar points of any crystal, even of the great rock crystal, to the most sensitive suspended magnetic needle, they never disturbed it in the least; it remained motionless. On the other hand, I suspended a large crystal (free from iron), for instance one of selenite, by the middle, with a twisted, very fine, silkworm thread, so that it swung with its long axis horizontal, placed it under a glass shade, and laid a magnet quite close to it; but this exhibited no action, and no kind of turning occurred.

I wished to see whether a polar wire would act upon a suspended crystal as upon a magnetic needle. I arranged a small voltaic pile of a few elements, each of about ten square inches surface, and connected the poles by a stout copper wire. I then suspended a selenite crystal, free from iron, and about four inches long, by a silkworm thread, so that both poles were free to move in the horizontal direction. When approached to a horizontal part of the polar wire, the crystal and wire were indifferent, and not the slightest visible reaction took place.

40. It still remained to be investigated whether the crystal would induce a momentary current, like a magnet, when brought near a conducting wire. I formed a helix of about twenty-five turns of strong, covered copper wire, and connected it with the couplings of an extremely delicate Schweigger's multiplier, the well-known differential galvanometer: when I rapidly inserted into the helix a selenite or rock crystal, each of several inches long, the astatic needle did not exhibit the slightest divergence. When withdrawn the case was similar, the needle was motionless; the weakest magnetic needle that I substituted for the crystals, in a counter-experiment, immediately produced a divergence of twenty-five degrees.

41 . The relation to terrestrial magnetism was here a question of the greatest importance. We have some old researches by Hauy, Biot, and especially Coulomb, in which, not indeed the proof, but the possibility is made good, that all bodies may possess magnetism to some extent, or are capable of acquiring it. Those of Hauy, (Mem. du Mus. Par. 1817, p. 167) may be passed over. M. Biot, in his essay on this subject (Gilbert's Annal. v. lxiv. 395, 1820,) is uncertain whether it is magnetism; or, as he interrogatively expresses it, " some other analogous force," which acts upon bodies. But in this treatise also we find throughout only such bodies denoted as more or less evidently contain iron. An experiment was made with two silver needles, one of which was made of chemically pure silver, the other of silver which had been melted with iron, and which, as no trace of iron could be detected in it by chemical analysis, was also regarded as perfectly pure. But the latter acted 416 times as strongly upon the magnet as the former. It was thence concluded that this also must contain iron, even though it could not be detected chemically, and that, as a general rule, inconceiveably small quantities of iron are always sufficient to give a body the capacity to acquire magnetism; indeed, that, consequently, even the needle made of chemically refined silver must have retained traces of iron. The most detailed account of these matters was read by Coulomb, before the French National Institute, in the year 1802 (ext. in Gilbert's Ann. xii. 194): in this he left the question unsettled whether the bodies which he tried were free from iron or not, and Gilbert remarks, with reason, that they scarcely could be. The experiments consisted essentially in this: needles of about one-third of an inch long, suspended by silk filaments, were brought between the magnetic poles, and made to oscillate previously and afterwards. The number of oscillations in the same time was always smaller previously than when they were counted between the poles; and thus the effect of the magnet was indicated. But what effect? one must ask. And every one must see that it may be one of three kinds:-1. Dependent on the presence of iron in the bodies. 2. On the bodies themselves. 3. On " another analogous force:: as M. Biot conjecturally expressed himself. The decision of these questions, so far as they bear reference here, appeared to me to require a uew direct experiment. I possessed crystals, especially of selenite, which acted upon all the patients as strongly as a magnetic bar capable of supporting five to seven lbs. A bar of this kind, suspended by a common linen thread, invariably arranged itself in the direction of the magnetic meridian. If, then, the peculiar, equally powerful force, which resided in the crystals, were the same as that in the magnet, the crystal when freely suspended ought to arrange itself in the meridian. To ascertain this I freely suspended various crystals, free from iron, and in particular the selenite of two inches long, by a silk thread, three twenty-fifths of an inch long, and untwisted, just as it had been wound off from the cocoon, and I brought these under a glass shade. They stood at rest for several hours, but never in a direction toward the north, or indeed in any determinate direction whatever. When I turned the point of suspension a quarter of a circle, the crystal was also diverted ninety degrees after some hours' rest. I could thus bring it completely into any direction I pleased. Therefore not the slightest opposition to the force of torsion of the finest silk filament occurred, and the crystal force does not endow its conductor with the slightest directive power; it does not stand in any relation of direction to terrestrial magnetism.

Consequently, as on the one hand the behaviour of the magnet and of the crystal to animal nerves was exactly the same, so on the other hand, to iron, to the electric current, to the opposite poles of the magnet and to terrestrial magnetism, it was wholly dfferent.

It is therefore established that, the polar force which resides in crystals, and renders its existence manifest by sensuous excitations of a peculiar kind, in the healthy and diseased animal nerves is not identical with the magnetic force, as we at present know it. It does not attract iron, does not act upon the magnetic needle, is in its strongest concentration incapable of exerting the slightest power of magnetically attracting iron, in the smallest steel fibres, does not influence the polar wire when placed in the helix, does not produce any induced current, and does not obey terrestrial magnetism.

On the other side it holds good that, the magnetic force, as we at present know it in magnetic iron-ore and in the magnetic needle, is associated with that force which we have just become acquainted with in crystals. For since the magnet acts upon animal nerves in the same way as crystals, it possesses, in addition to its own properties, which are wanting in crystals, at the same time that force also which resides in crystals.
From which it further necessarily follows, that the force of the magnet is not, as has been hitherto assumed, single in its nature, but of two kinds, since to the older known one is now added a new unknown one, distinctly different from the former,—that of the crystal. It may appear divested of the other properties of the magnet, and in nature is displayed in a separate condition by the crystal.

The phenomena which the magnet presents may be divided therefore into two sections, which become complicated with each other in their manifestations; and it will he necessary to subject a portion of the great store of them which science has accumulated, to a process of revision.
I now instituted investigations as to the nature of these new properties of crystals. In the first place, I sought to make out whether this force might be transferred, conveyed, or accumulated? Whether, and what analogies, it possessed in these respects to magnetism and electricity, which can be conveyed, displaced, conducted, and concentrated. Since first of all I possessed no other magnet but the excited animal nerves of healthy and nervously diseased persons, while the excitability of the healthy persons I have hitherto met with is so weak that a distinction by degrees did not warrant sufficient accuracy, I was compelled to apply myself to the more acute sensations of the sick. For since the persons with whom I undertook the researches, placed in the most varied circumstances and suffering from different diseases, not only were consistent in their sensations, but also the statements they made, when arranged under a theoretical point of view, harmonized with each other, every reason existed to attribute value to them. I am fully aware of the objections I shall meet with here; but with the cautious naturalist, who keeps his certain steps within the boundaries of experience, they have no weight. All that we investigate of the outer material world we must, to the end, gather by our senses; we have no other instrument of perception.11 We count five senses and no more; but we are already sufficiently aware that things go on in nature, and, in fact, around and in us, which we are unable to detect, only because we possess no instrument for their perception. In every infinitely small interval of time countless electrical movements proceed around us; we do not perceive the slightest trace of them. If any one were to come down from the clouds who had a sixth, an electrical sense, with which he could detect and could describe the finest electrical changes around us, with the accuracy that we do the phenomena of light by means of our optical organs, should we not eagerly listen to his teachings, and ask him thousands of questions, to clear up and extend our knowledge? One born blind, who has never had a conception of light and colour, allows himself to be led by one that sees; and when be always finds the stone, by feeling, which the seeing guide had forewarned him of, he believes that the seer has eyes, which enable him to see things. Now, a nervous patient is one of this kind, in whom a sensitiveness for electrical and magnetic movements exists, and with which is unfolded to a certain extent a peculiar sense, so to speak, of which, as it will appear, the healthy are deficient. Among the nervously diseased, referable here, I do not mean directly somnambulists, sleep-walkers, &c., but, as a general rule, most persons who suffer violently from spasms. The somnambulists are only those in whom these disturbances of the normal condition of the nervous system have reached the highest degree, and in whom the excitability has reached its maximum. They give us the strongest testimony of the reactions, and show us the most delicate differences; but they are not absolutely necessary in the researches to which I devoted myself. Miss Nowotny, on whom I made my experiments, was far from being a somnambulist12 during the whole time of my six weeks' study; she only suffered from cataleptic spasms. Miss Maix never exhibited a trace of somnambulism. The surgeon, Mr. Schmidt, of Vienna, who experienced the most striking effect from the crystals and the magnet, as well as the terrestrial magnetism, was a young, otherwise perfectly healthy man, who merely was attacked by cramps in one arm for a short time, through exposure of one side to cold. And the sensitiveness might be thus traced onward to the healthy, who only felt the pass of large crystals upon sensitive parts, like a cool breeze. Finally, there was a further distinction even among these, that some felt the cooling strongly, others more weakly, some not at all.

If, therefore, all this stands in regular connection, cause and effect cannot be disputed away, and, in my opinion, it would not be well done to throw away results which may become so valuable a key for the investigation of truths of nature, in those branches of physics and chemistry where she seems to wish to conceal her mysteries from us most obstinately. The singular sense, the peculiar irritability of nervous patients, is chiefly directed to magnetic phenomena; they are an invaluable reagent while we possess no other. They are not vague sensations, as has hitherto been often believed, and as like those by which many physicians and visionaries have brought reproach upon themselves; but everything follows rule and law, and these are soon discovered, when one does but investigate them intelligently, trace them with the aids of physical and chemical knowledge, and apply to them the touchstone of experimental criticism.

I could not avoid this digression; it is indispensable to the definition of the stand-point of these researches. I now turn again to the questions, whether the peculiar force which displays itself in crystals is communicable, conductible, and condensible? When the most incongruous things, a piece of wood, a glass of water, leather gloves, paper cuttings, or any thing else, were rubbed with the pole of a crystal, every sick patient detected without delay, when placed before them, the difference between such and others which had not been rubbed. The sensation was sometimes a cool, sometimes a warm feeling, perceived by the hand in which the object was placed; and this gradually increased until it became unpleasant. The conveyance upon paper was found to be the weakest. Miss Sturmann did not feel a book which had been once rubbed with the Jarge rock crystal; often rubbed, scarcely at all. Finally, when I had held it for a time in contact with the point of the crystal, and at once quickly placed it in her open hand, she felt a slight warmth. A piece of porcelain touched with the crystal-point, felt cool to her. A German silver conductor of an electro-magnetic apparatus, when treated in the same way, she felt very warm. A piece of soft iron, a piece of a blue steel saw blade, a hard steel file, all at first found indifferent, produced a sensation of heat in her hand after the crystal point had been drawn over them. I placed my hand in her's, first let her get accustomed to it, then took it away, and drew it backward and forward a few times above the point of the great rock crystal, and then again laid it in her's: the patient at once felt a great difference; she now found it far warmer; and this apparent elevation of temperature decreasing, for more than four minutes, during which I repeatedly extended it to her for trial. A similar series of experiments were gone through with Miss Maix, and subsequently with Miss Reichel. The charge was here conveyed to copper, zinc-plates, linen, silk stuffs, and water. They gave wholly similar results. Miss Atzmannsdorfer perceived immediately whether the German silver conductor had been previously in contact with a selenite crystal or an amorphous body, and particularly whether with the warming or cooling end of a crystal the heat conveyed was stronger or weaker, or replaced by cold. The crystallic force may therefore be transferred or conveyed to other bodies. It may be transferred to iron and steel, and, at the same time, these bodies, so charged, do not attract iron filings, as I have already shown above.13

I endeavoured to ascertain whether this conveyance could be effected, like that of magnetism, by rubbing from pole to pole, or, like that of electricity, by single points. It proved to be indifferent whether I rubbed the object in the direction of its length, or kept any point whatever for a short time in contact with the point of the crystal; the warmth or coolness thus produced were not found to differ. A large crystal, when the point was applied to a glass of water, produced magnetized water, as well as a horse-shoe magnet.

46. The question now was, whether a coercive power existed in matter, whether this charge was persistent or transient, and after what intervals of time? I charged various objects,—the German-silver conductor, the steel file, the soft iron, the piece of porcelain, and the book. The last soon lost its power. The piece of porcelain tried on Miss Sturmann retained it two minutes, the conductor five minutes, the iron the same, and the steel ten minutes. In this operation I did not take the objects in the free hand, but moved them backwards and forwards in a fold of paper; when the patient bad taken hold of them, I made her lay them down, and wait till the sensation which continued to thrill through her hand had disappeared. This required about a minute. Then I made her take the object up again, without having touched it myself, and continued thus until the sensations of heat or cold were no longer produced. From this it follows that the retention of the charge, under the above circumstances, is not, even at night, of long, but of short duration, and, indeed, at most of ten minutes; that the charge soon disappears again, and, unlike magnetism, it cannot be permanently ingrafted upon steel. Since the iron filings fall from an iron bar which has been placed within the sphere of distribution of the magnet directly and instantaneously when the magnet is removed, but here an effect of accumulation does occur, although but for a short time, the question must be answered thus: that some, even if weak, coercive power over the crystallic force does actually exist in all bodies, which for magnetism, so far as we know it at present by its polar effects, is not the case, since the coercive power, according to our actual knowledge, is limited to an exceedingly small number of bodies; in fact, according to the most recent researches, strictly to iron and nickel.14

47. Is the crystallic force capable of being isolated, arrested, or is it universally distributed through matter? The first experiments were made with Miss Sturmann, who, though sensitive to the magnetic excitement, was less clear in her perception of it as to the distinction between warmth and cold. When I placed a book upon her hand, and brought the point of the large rock crystal upon it, the hand felt nothing of it through the book. Since she had previously felt the approach of the crystal to the inside of the bare hand at a distance of 18 or 20 inches, while now the distance was no greater than the thickness of the book, that is, four-fifths of an inch, this experiment showed that a thick mass of paper was a substance capable of arresting, at least for a short time, the action of the crystallic force upon the nerves of this patient. A piece of deal board acted in a similar way, but less perfectly.15 After a short interval the alteration of temperature began to be weakly perceptible beneath it. Eight folds of printing paper soon allowed the force to act through them; four folds of woollen stuff scarcely offered any perceptible obstacle. A porcelain dish, lying in her hand, touched on the upper side with the point of the crystal, was felt to be cool when I turned it over after the contact. On the contrary, an iron plate gave a warm sensation, when placed on the hand, as soon as I brought the crystal near; when I put it in contact the effect was like a shock, ascending through the elbow-joint to the shoulder.16 Various metallic wires, held in the hand by one end and touched with crystal points at the other, gave sometimes warm, sometimes cool sensations, without exception. I placed one end of the German silver conductor in her hand, and placed the other end in contact with the point of a small crystal; the sensation of an alteration of temperature shot instantaneously from the hand to the elbow joint; when I operated in the same way with the large rock crystal, it ran up as far as the shoulder, and produced cramp-like sensations.

When I subsequently repeated the same experiments on Miss Marie Maix, action took place through all bodies without exception, only it was more rapid through metallic, more like a shock, so to speak, than with vegetable substances, tissues, &c., which required a short interval of time for the effect. I made experiments with wool, silk, glass, and zinc on Miss Reichel. The transmission through wool required a short moment of time in a cord 40 inches long; but with silk, glass, and zinc, it was instantaneous, and of immeasurable rapidity. My experiments on the very sensitive Miss Atzmannsdorfer furnished similar results; brass wire, the German silver conductor, glass tubes, leaden bars, platina foil, bar iron, gold threads, and copper plates, which I placed in her hand, were instantaneously traversed by the force which passed into them by contact with the crystal. The conclusion is, that the crystollic force acts through all bodies, but in different degrees.17 Paper, wool, and wood, render the passage difficult, at least for a short time; porcelain less so; silk and glass are perfect conductors. Metals permit the passage not only on actual contact, but in slight degrees even before the contact, on mere approximation; but on contact an immediate action ensues. So far as these preliminary tests allow of a conclusion, they indicate that the difference of conducting power of bodies depends less upon their nature than on their continuity. All tissues conduct worse than solid bodies; cotton and wool worse than wire, silk, &c. The completeness and rapidity of the conduction were experienced in different degrees by patients of different states of sensitiveness, in such a way that while to the more sensitive everything is permeable, with the less sensitive occur distinctions among the bodies in the degrees of the permeability by the crystallic force.

48. I still wished to test the magnitude of the capacity for being charged. I made passes and contacts on the conductor and the steel file a varying number of times. One pass acted evidently more weakly than several; but when I had occupied a minute in the charging, it attained a magnitude which, under the given circumstances, was insusceptible of further increase, at least of an increase of strength of the sensations of warmth and cold thereby produced on the hand of the patient; to which corresponded the frequently repeated trials of the persistence of the charge, which never endured more than about five minutes, however much time I might have consumed in it, excepting only on steel and water, where it was felt about ten minutes. The charge was not effected instantaneously, but increased during the contact for a short time, and then attained its maximum. This capacity for a charge was satisfied in a few minutes.18

49. In reference to the magnitude of the force and its relation to the size of the crystals, the experiments showed that a small crystal, from the size of a lentil to two inches long, if of gold, rock crystal, selenite, diamond, or hornblende, was weak, and only actively perceived in the reversed pass upward; that from this point the force increased with the size of the crystals. The exponent, of course, could not be made out as yet.19

50. The distinction of the poles, in reference to their power of affecting the nerves, was expressed by an opposition of cold and heat. Almost in every case the crystal produced cooling with one pole and warmth with the other when drawn over the hand. Miss Nowotny, and the surgeon Mr. Schmidt, in the upward pass felt, like the healthy, a cool pleasant breeze; in the downward pass a not disagreeable gentle warmth. I tried crystals of tourmaline, arragomte, rock crystal, selenite, and cleavage forms of Iceland spar and tellurium, on Miss Sturmann. All presented a stronger cooling pole, and a weaker warming one. This difference was very clearly marked with Miss Rcichel, who distinguished the poles of all crystals, even at some distance, by a sensation of cold and heat; and this with very great accuracy. As I have already mentioned, Miss Atzmannsdorfer felt it most strongly. But even healthy persons, e. g. Prof. Endlicher, as already mentioned, Mr. Studer, my servant Johann Klaiber, and others, distinguished the two poles of all crystals very accurately, even of very small ones. The opposition of the two poles of crystals, therefore, expressed itself upon the nerves at once by slight heat and cold. I shall hereafter detail some other contrasts.

51. The high degree of distinctness which the excitement possessed in sick persons is worthy of notice. Not only do they perceive it universally on the masses of bodies which are brought to them, but they clearly perceived that there are points at which the force is concentrated. Miss Nowotny pointed out to me very definitely, in every crystal, the spots where effective poles were situated, which she very quickly discovered with the tips of her fingers. In double crystals the axis always passes through the line of junction of the two crystals. Miss Maix, Miss Sturmann, Miss Reichel, and Miss Atzmannsdorfer, had the same power, in some cases with still greater readiness. Even Mr. Schuh and Mr. Studer accurately felt out the points on large crystals, and their observations all agree accurately with one another.

52. The crystal-electricity, as excited in tourmaline and other minerals by heat, does not exhibit any perceptible effect upon the nervous excitement produced by the crystallic force. I heated these bodies to different degrees, but they produced no evident modifications in the effects.20

53. Does the crystallic force stand in no relation of direction to terrestrial magnetism? Starting from the manner in which crystals are built up, one would be induced to conjecture that the two forces are really to a certain extent independent of each other. Whoever has seen a nucleated mass of quartz crystals broken into, in a mine, and noticed how they stand in all directions, cannot have overlooked that the entire cavity is clothed on all sides, above and below, with crystals whose axes are directed in every possible direction. But without going into a mine, this observation may be made at once in a cabinet of minerals, upon the well-known balls of chalcedony, the cavity of which, i. e. the nucleus, is clothed all over with crystals of quartz and amethyst: I have never been able to detect anything like an uniform direction. Other crystallizations, again, which are grouped in stalk-like heaps around a common central point, like natrolite, zeolite, mesotype, arragonite, pharmacolite, &c., form tubercular globules, the rays of which spread out in all directions, and no indications lead ns to imagine an influence or any kind of external directing force on their formation. Our own crystallizations, as they go on in our laboratories and manufactories, are in like manner usually altogether confused; prussiate of potash, alum, sugar of lead, sugar-candy, &c., deposit their crystals, in large vessels, without any choice of direction. This appears to agree with the indifference which free crystals observe towards the magnetic needle and the polar wires. On this side, therefore, the crystaiic force is independent of terrestrial magnetism, in reference to the direction of its structures.

54. Since now the crystallic force shows itself to be free from that attraction to inorganic substances which so remarkably distinguishes the magnet from all terrestrial things, it must, on the other hand, prove the more striking,—nay it seems to claim the highest degree of interest in natural science,—that it shares with the magnet the singular power of attracting living organic bodies. For as I have already minutely described, I saw the effect produced by the magnet upon the cataleptic Miss Nowotny, repeated when she was brought in contact with the points of large crystals. It contracted her hand, in some cases produced cramp, and attracted her hand to follow it, not so strongly as a large
magnet, but exactly in the same manner as a weak one. I am certain that if I had possessed a crystal large enough, her hand would have adhered to it, both in the unconscious and conscious state, just in the same way as it did to a strong magnet. This elective affinity of the crystallic force to attract living and not dead matter is the most extraordinary character it displays, and points to the powerful connexion in which it stands with the inmost essence of that which we call life, and respecting which, if I am not most grossly mistaken, it promises closely imminent and most important results.

55. In a former treatise I gave an account of the light which issues from the poles of a strong magnet. After that observation, it was very natural to imagine the possibility of the same at the points of crystals; indeed, there was great probability in the anticipation. I therefore instituted an experiment with the heightened vision of Miss Sturmann. A room was made as dark as possible; she entered, remained some time, till her eyes became accustomed to the obscurity, and then I placed before her the large rock crystal. She actually at once perceived a florae-like light over it, half the size of a hand, blue, passing into white above, remarkably different from the magnetic light, which she described as much yellower and redder. The experiment was repeated twice on the following night. In order to obtain as complete conviction as possible before Miss Sturmann came into the darkened room, I placed the large eight inches thick rock crystal upon a place which she could not be aware of. As soon as the obscurity was fully restored by shutting the door, she in every case immediately detected the place where the crystal stood, and saw the flaming light exactly the same in all these three experiments. She described it as somewhat resembling a tulip in shape, and beginning below with a curve directed outward, like one of the petals, or like a candle-flame, but then soon taking an erect position and rising to about the height of her finger's length. She again spoke of the colour as blue, passing into perfect white above, and in such a manner that isolated scattered streaks or filaments of a reddish colour ram up in the upper part of the white. The flame was moveable, in a waving and sparkling condition, and threw a light glare over the support on which the crystal rested, of the diameter of almost forty inches, just as a magnet had done, when flame-like appearance and light radiating from it could be clearly distinguished. From her I turned to Miss Reichel, and placed various crystals before her in the dark. She everywhere found the flaming appearances bright, surpassing those of the magnet in brilliancy of colour and regularity of form. The light was with her visible not only over the poles of the crystals, but even in the interior of their substance. She described the flame over the poles much in the same way as Miss Sturmann, but the appearances of light in the interior essentially different from this. She said that they were of peculiar, star-like forms, which assumed different shapes when the crystals were turned. It was evidently the crystalline structure of the stone, its lamination in different directions, which caused the production of luminous appearances and internal reflections, such as of course could not exist in this way in a steel magnet. She furnished me with drawings of the lights of large and small crystals, which represented most astonishing appearances. I reserve all the various magnetic luminosities, which I became acquainted with, to bring them together hereafter in a special comparison, and shall give figures of Miss Reichel's drawings of the crystallic luminosities with that. Miss Maix also, whose calm and accurate mode of observation I especially valued, for many nights that I left the great rock crystal upon her stove, beheld in her sleepless hours the beautiful spectacle of a whitish star, half the size of her hand, on the apiculated summit. Miss Atzmannsdorfer in all cases pointed out the luminous pole in the dark, in a number of different crystals, and placed them in a series for me, according to their strength.

Since, then, all the crystals, which I had subjected in such great number to the test, exhibited the same reactions in reference to that peculiar force, which they manifested at their poles, as occurred in its maximum in a large rock crystal, one is led to the conclusion that crystals in genera, like the magnet, emit a fine flaming light from their poles, usually invisible to healthy eyes, but seen by those of excited nervous patients, in whom all the senses exist in an unusually acute condition. I need scarcely mention that this bears relation to the luminous appearances frequently observed during crystallization itself by chemists, which have long found place in the text-books. The nature of these radiations has not yet been explained; they have generally been assumed to be electrical, because they look like such, but no direct proof exists. Prof. H. Rose, however, has lately shown that this light is not connected either with heat or electricity, since neither the air-thermometer nor the telescope is affected in the least when dipped in a crystallizing solution of substances which exhibit the highest known degree of evolution of light in the moment of crystallization; for example, sulphate of potass and soda (Poggend. Annal. LII. 443, 585). But now that we have become acquainted with the permanent luminosity of crystal poles, which at present exhibits no agreement with electricity, but indeed a great difference, it becomes highly probable that the said light is dependent, not on electricity, but on the evolution of phenomena of crystallic light, and that circumstances arise in the sudden conveyance of the molecules suspended in the fluids into solid crystalline bodies, under which the crystallic light becomes so concentrated as to be visible to common eyes. What this light is, which like sunlight beams continuously, without in the least diminishing the body from which it radiates, whether it is a vibration propagated in the surrounding fluids, I leave here untouched. We assume that the atoms, still more the molecules of matter, are polar; we regard them as the elements for the construction of the crystal. Is their arrangement into a large solid crystal; which again has its own polarity and is luminous at its poles, a sum of all these little polarities, and are its poles an expression of this, as the open poles of a voltaic pile afford the sum of the shares of electricity of all the individual elements? Is a crystal a pile for the crystallic force, as the voltaic is for the electrical? These are approaching questions reserved for further investigation; meanwhile the consistent observations here made, and often repeated, on five different sick persons, will soon find confirmation in other places and by other observers; only I caution them not to undertake the experiments with somnambulists in the sleep-waking condition, but either with others, not somnambulist, nervous patients, or, if none such can be found sufficiently sensitive, to take the somnambulists only in the awake, conscious condition, when their senses are clear; and not to make use of the sleep-waking condition at all, or at most solely for the control of the former. I have never employed the patients in the magnetic sleep or somnambulism in my physical investigations, but when in this condition have left them in the hands of their physicians, and contented myself with the position of a spectator. To prevent errors, I again remark, that when it is wished to repeat my experiments, the place must be completely darkened, so densely that even after a long stay in it, after one or two hours, no trace whatever of light can be detected; finally, the crystal must be very large, for mine, as I have already mentioned, was not less than eight inches thick, and proportionately long. With those, however, who are strongly sensitive, smaller crystals will answer the purpose, since Miss Reichel and Miss Atzmannsdorfer saw light issue from almost every crystal, especially from compounds of sulphuric and fluoric acids, which in all cases surpass rock crystal of the same size.

56. All these researches finally unite to show, that the peculiar force of crystals here developed, opens a new page in the book of dynamics,—that it certainly falls within the general laws of these, but possesses its special code, to study which, and bring their axioms to mathematical expressions, must be henceforth one of the tasks of physics. It will be above all desirable to find some universal inorganic re-agent upon it, to discover an instrument of detection and measurement, which shall free us from the often worse than painful dependence on sick persons, hospital patients, and unscientific persons of all kinds.21

RETROSPECT.

a. Every crystal, natural or artificial, exercises a specific exciting power on the animal nerves, weak in the healthy, strong in the diseased, strongest of all in the cataleptic.

b. The force manifests its abode principally at the axes of the crystals, most actively at its opposite extremities; it therefore exhibits polarity.

c. It emits light at the poles visible to acutely sensitively eyes in the dark.

d. In particular diseases, it attracts the human hand to a peculiar kind of adhesion, like that of iron to the magnet.

e. It does not attract iron, does not cause any freely moving body to assume directions referable to the terrestrial poles, does not affect the magnet, does not induce a galvanic current in wires, and consequently it is not a magnetism.

f. It may be charged and transferred upon other bodies by mere contact.

g. Matter possesses a certain coercive power over it, but only for a limited time, during which the transferred force disappears.

h. Matter has a power of conducting it, in different degrees, in proportion to the continuity of bodies.

i. The capacity of bodies to receive a charge is in direct relation to the strength of the crystallic force.

k. It expresses itself quantitatively different at the two poles; so that, like the magnet, it produces, as a rule, sensations of cold at the pole corresponding to — M, at the pole corresponding to + M of gentle heat. In regard to quantity the northward pole is stronger, the southward pole weaker.

l. Warming the crystal has hitherto produced no essential modification.

m. This force of crystals is contained in those exhibited by the magnet; it constitutes therefore a separable part of them, capable of being isolated.