Chapter 3

Techniques of validation when touch is allowed
Most of the experiments I shall describe are on the measurement, by means of sensitive equipment, of physical effects produced on metal specimens which the metal-bender is not allowed to touch during the entire session. However, before I settled down to such experiments, I made observations of bendings and fractures produced merely by stroking, in order to satisfy myself that manual force was not being widely used to bring about the bending, either intentionally or unintentionally. These observations are not as easy as they sound, particularly when curved household objects such as spoons are used. Clearly, small changes in the curvature are difficult to detect without precision measuring equipment. The use of a curved comparison template such as a similar spoon is not a particularly sensitive or satisfactory method. I therefore used flat strips rather than cutlery, and am surprised that some other observers are still watching children stroking spoons! This chapter is in part directed at those who wish to play a part in psychic research, but approach the subject with very little experience or technical knowledge.
The normal bending of a metal strip is brought about by loading, most simply the three-point load, which produces a uniform cube-law curvature, and the four-point load, in which the centre section is free from stretching force, and a square-law curvature is produced. When the loading (stress) is light, the deformation (strain) is elastic, and is proportional to the load. When the loading is increased beyond the yield point, the deformation becomes plastic, that is to say, permanent rather than temporary. Deformation progresses until work-hardening prevents further distortion. If the loading is sufficiently large, the work-hardening will be insufficient to prevent fracture.
The first task which an observer faces is to become thoroughly familiar with the magnitude of the forces required to bring about normal deformation; he must also become familiar with the appearance of human hands and arms when such forces are being exerted.

Since it is a moment (force multiplied by distance) which produces deformation, both the yield strength and the length of a metal specimen need to be considered. We also need to know the limits of human strength, using either two hands or a single hand. Systematic tests of large numbers of people were made by the French researchers. For a two-handed bend on a specimen 25 cm in length, the average limit of male strength is 25 Newton metres moment (25 Nm), and the average female limit about 15 Nm. The limits of children vary between 5 and 20 Nm. The record achieved by the strongest man tested by means of a dynamometer was 38 Nm on their 25 cm specimen.

When observing bending by stroking, we need not insist that a bend beyond human strength be produced (unless there is a large gap in the observation), but only that the human strength required should be easily recognizable when it is being exerted; physical strength between one-half and two-thirds of the limit is easy to recognize. Unfortunately opinions occasionally differ about what is recognizable as manual force, even when studying videotapes; but a consensus opinion is of value. I have carefully studied a videotape of a bending by the French metal-bender JeanPierre Girard, under strict protocol, of a specimen that he was able to deform by an amount that would require 14 Nm; although his stroking action looks beyond suspicion to me, and to many who have seen the tape, a French physicist of distinction has claimed that the finger forces could have been rendered especially strong by athletic training.

For a single-handed bend the situation is more complicated. When a specimen is held and stroked between fingers and thumb, parts of the specimen are concealed from view by parts of the hand. This screening is minimized when the observers view from different angles and different heights (e.g., with a mirror-surface table). A three-point load can most easily be applied to a specimen, using one hand, by (a) the ball of the thumb, (b) the first or second joint of the forefinger, and (c) the base of the palm. The bend will then be centred on the point of application of the forefinger. If the specimen is only about 5 cm long (e.g., a latchkey), then it is not possible to apply a three-point load in this way; instead the thumb and two fingers would be used; in this operation much more of the specimen is exposed to view. I have used latchkey specimens for this reason. On occasions I have noticed that paranormal bending takes place beyond the end of the thumb and fingers, which would be impossible under normal bending from a physical three-point load. When the bend is gradual, it is difficult to be certain that there is no physical three-point load throughout the time of bend. But on one occasion a single crystal of zinc was stroked between the fingers and thumb by Graham P., under good conditions of observation; I observed an instantaneous cleavage beyond the end of the fingers and thumb. The end of the crystal dropped to the table, leaving the remainder of the crystal exposed, projecting beyond the fingers and thumb. A sudden event of this sort enables the observer to be certain that the position of cleavage is not between the two outer loading points and, therefore, that physical force of the fingers and thumb could not have caused the cleavage.

It has been pointed out that although latchkeys are excellent for exposure for bending in one hand, they are relatively easy to bend if one end is gripped in a slot in a piece of furniture, or in the open end of a metal tube; the observer must watch carefully for such things. Latchkeys can be bent with two bare hands only by a strong man, and I have never encountered anyone able to bend one using one bare isolated hand. But it is possible to do it by pressing one end of the key onto a hard surface, using a single hand only; one latchkey has also been linked through the hole of another to increase the leverage.
For a one-handed bend using fingers only, the limit of human strength is about 10 Nm, depending on specimen length. Another operation is possible to a metal-bender: the production of two bends simultaneously in a long (4050 cm) specimen held in both hands. One bend is produced under each hand, so that an S-configuration is formed Any tendency to produce only a single bend between the two hands should not be accepted. Two bends each requiring >= 10 Nm can then be accepted as validation.

The tight twisting of the handle of a stainless steel dessert spoon (see chapter 1) through 180° requires typically a torque of 78 Nm. This is beyond human strength even if the handle of the spoon is held rigidly, for example in the keyhole of a door; the typical male human limit is 4 Nm. Thus the tight twist is good validation under observation, even though few metal-benders are able to achieve it, as will be further discussed in chapter 11. The stainless steel teaspoon requires 5 Nm. whereas the limit of torque that can be exerted on the bowl by an adult male is typically 2 Nm

A few examples of well-observed bends will now be given. A latchkey bend by Uri Geller has been described in chapter 1, and I have observed others by Uri Geller and by Nicholas Williams and Andrew G., including fractures. I have observed a 23 Nm metal bar bent by stroking by JeanPierre Girard, under good protocol; a moving picture exists of this event, also described in chapter 1. Dr Crussard and Dr Bouvaist, whose researches with JeanPierre Girard are described in chapter 13, have observed his bendings of several metal bars of up to 75 Nm yield moment. Uri Geller, tested under similar conditions, has achieved an 80 Nm bend. I have offered an AU4GT4 aluminium alloy bar to Julie Knowles and she has obtained a 45 Nm bend; although there was a gap in the observation, there were no visible signs of force being used on the carefully polished bar, and it needs more than twice her physical strength.
We have seen that for observation (with or without video-camera) of bending by stroking, the specimen should be chosen to be sufficiently strong to require considerable muscular effort to deform it; with careful watching this effort can be recognized by the observers; at the same time the use of absurdly strong specimens is unlikely to result in there being any measurable deformation. The most sensitive methods of measuring permanent deformations are by means of a micrometer gauge of suitable design, or by the unevenness of roll of a cylindrical bar on a flat surface. In the latter case a deformation of about 0.10.2 mm can be detected; in the former, one may achieve 0.01 mm sensitivity. The specimens should initially be accurately machined and the residual deformation measured. The use of matching cutlery as templates is much less accurate.

The preparation and yield-testing of metal specimens require standard metallurgical and engineering techniques. Destructive yield-testing can to some extent be avoided by making use of the fact that for many alloys the hardness (a nondestructive test) is a good indicator of the yield strength.

When metal-bending by stroking is to be observed, there are two central problems of validation.(16) One is that the specimen be prepared and identified beforehand, and examined and identified properly afterwards. The other, as we have seen, is that the observation of absence of serious normal force should leave no room for doubt. Under no circumstances should the observer allow himself to be manoeuvred into a situation in which (for example, because of unidentified specimens) sleight of hand could be used for substitution. This is possibly the most difficult operation for an observer to detect, even if he is practised.

The object of visual observation and videotape recording is to determine whether or not physical force has been entirely responsible for the bending, and to determine whether the specimen or any other object has been substituted at any moment. Visual observation is a deceptively simple exercise; it requires careful preparation and practice to perform well. The best number of observers is three or four; any more will introduce crosscurrents which distract the attention; in addition, the field of view of each observer is diminished. Fewer observers would certainly ensure that the field of view of each was very large, but probably larger than each could successfully watch. There should if possible be more than one observer, since the chances of catching a sleight of hand are increased by the presence of several. Attention should be paid to good lighting to minimize shadows, to the background surface and to the avoidance of all distractions, whether originating from the subject, from the observers or externally. The maximum time for which a really high standard of visual concentration can be maintained is about two to three minutes. If the event takes longer than this, then undoubtedly moments of lapsed concentration will occur, increasing in frequency as time proceeds, thereby increasing the probability that the concentration of all observers will lapse simultaneously.

An important consideration is the width of field of view which it is required to observe; this should not be larger than about 0.05 steradian, (The steradian is a unit of solid angle; about fourteen of them subtend the entire surface of a sphere from its centre.) otherwise motions of eyes become unsuitably large. With chart-recorded experiments this presents problems, since there are several widely separated points which must be simultaneously watched. But the observation of bending of a metal specimen held in a stationary hand, or situated within inches of the hand, is much simpler, since all that is necessary is to concentrate very hard on a narrow field of view. A distance of about two or three feet between the observer’s eyes and the specimen enables the maximum of detail to be recognized without widening the required field of view unduly. An important task of the observers is to ensure that the intended and identified specimen remains in view from the moment it leaves the possession of the investigator until the moment it is returned to him.

The purpose of recording by videotape is twofold: to obtain records by means of which a physical event can be studied repeatedly, and to obtain records to increase the credibility of the investigator. Although the achievement of each purpose is important, the temperamental nature of the metal-bending ability is such that some investigators (myself included) do without the luxury of videotape recording for most of the time. It is important to assign the correct priority, as between experimentation and moving picture production, and to maintain a suitable proportion of each. It is my experience that if the experimenter is also the cameraman, then he cannot also perform adequately as observer. The technical operation field of view, lighting, panning, etc. occupies most of his time. Observer and cameraman should therefore be two different people.

When a videorecord is taken, the field of view of the action should also contain a stop-clock, in order that the record should be seen to be in real time; no cuts have been made. Another technique, employed by Harry Collins, is to include a burning candle, whose flame readily shows up any cutting.

Specimen identification and examination is of great importance. The primary purpose of examining a specimen is to identify it before and after bending, and to measure the magnitude of distortion. The most powerful simple identification is by accurate weighing; an accuracy of g can be achieved on a chemical balance. What appear to be identical specimens exhibit different weights, even if only by a few milligrams. Considerable careful machining would be required to prepare specimens giving identical readings on the chemical balance. Weighing will also detect weakening by filing, chemical action, condensation of moisture and perspiration.

However, there is another purpose in making detailed physical examination of a specimen. Changed physical properties might be considered as possible indicators of the paranormal character of a bend. They would be valid indications only if the structure of the metal were noticeably different, as between paranormal and physical bending. We shall enumerate examples of suitable physical properties that have been used for such tests. In most cases, the difference between paranormal and normal bends is undetectable, but there are several physical properties -magnetic and structural-which can be measurably abnormal in a paranormally bent specimen. In chapters 13 and 16 this will be discussed in detail.

The orientation of grains in a polycrystalline specimen can be monitored by X-ray reflection; at my instigation in 1974 Dr Paul Barnes and his students(17) made measurements on a brass latchkey allegedly paranormally bent by Geller, and found the data indistinguishable from those for the unbent parts of the latchkey. Mr Wälti(17) at the University of Bern has confirmed this finding, on other specimens.

In the following year micro-hardness measurements were made at my instigation by Dr Desvaux(18) on polycrystalline and single crystal specimens paranormally bent by our child subjects. The data (e.g. Figure 3.1) did not show extensive differences from those which would be expected for physical bending. Thus neither of these techniques is in general suitable for validation by examination of bent specimens.

A possible technique of validation by specimen examination is the study of paranormal fractures by electron microscopy. In our college Dr Paul Barnes and his students made electron micrographs of paranormal cutlery fractures, but although some features were found which would not be expected in normal fractures, the complications were such that recognition of a paranormal fracture from the electron micrographs was by no means certain. It was also reported by the late Dr Wilbur Franklin(19) that electron micrographs of paranormally fractured stainless steel spoons were similar to those of normal room temperature ductile fractures. It must be recognized that the study of fractures by electron micrograph is a specialization in itself. In chapter 11 the subject will be further discussed.

Figure 3.1 Hardness measurements on copper single crystal, of cross-section 5 mm square, bent under good observation by Graham P. The end of the ingot, bent under good observation by Belinda H., is shown on an enlarged scale
Also in the category of validation by proof of paranormal structural change are the experiments of Eldon Byrd, and later those of Bob Cantor(20) and Melanie Tokofoyu, on mechanical memory metals. The mechanical or shape-memory effect (SME), also known as marmem or martensitic memory, is especially strong in the near-equiatomic nickel-titanium alloys or nitinols. A marmem alloy is set up by machining or mechanical distortion to have a certain shape at a certain temperature. When it is plastically deformed, for example by manual force, at a temperature below the original temperature, it will revert to its original shape on heating to a temperature above the shape-memory transition temperature.
Eldon Byrd set up pieces of nitinol wire for Uri Geller to deform, which he did allegedly paranormally. On appropriate heating the original shapes were not achieved; new shapes were formed. This has been taken as proof that the action was paranormal in that it produced some structural change in the metal. It would be difficult to propose an alternative explanation with confidence. Later, nitinol specimens were exposed to a number of the British metal-bending children. Of these, half succeeded in destroying the mechanical memory and half did not.
When deformation of ordinary metals is unusually extensive, a simple validation technique using specimen examination becomes possible. We know from studies of stress-strain data that permanent plastic strains of greater than a certain value cannot be reached by the normal application of stress; this is because of the existence of a maximum in the stress-strain curve; when this is reached, the strain can increase rapidly until fracture results. The percentage strains which cannot be reached have been given as: aluminium 13%, soft copper 23% and mild steel 17%.
If such large strains are reached at the convex surface of a bent specimen, without cracking, then we know that some treatment such as heating to a high temperature, or paranormal softening, must have been necessary to produce the convex surface cracking. If crackless sharp bends of thick specimens through sufficiently small radii of curvature are obtained, then their existence points to the action of something other than normal force.
Neglecting humpback distortion, the strain at the convex surface of a circular bend of radius r at the neutral axis of a strip of thickness t. For a strip of width 2r twisted with pitch p, . Thus we may readily calculate whether the maximum strain has been exceeded; we have found it to have been substantially exceeded in bends produced by Andrew G. and Julie Knowles, and in twists produced by Stephen North and Andrew G. The twisted spoons produced by Masuaki Kiyota and shown in Plate 1.1a (1,4) fall into this category. It should be mentioned that Professor Uphoff has also observed the boy producing such twists on identified stainless steel teaspoons; first the metal was softened by stroking with the forefinger, and then a quick twist of the wrist produced the necessary (but much reduced) torque. Professor Uphoff has offered a monetary reward for a performance of this operation by normal means under his specified conditions. The circumstances under which Masuaki produced the twisted spoons for me are described in chapter 1.
Thus we are introduced to the conception that the paranormal phenomenon is not precisely metal-bending, but temporary metal-softening; during this softening, a smaller, sometimes a very much smaller, degree of manual force is necessary for permanent deformation. So we return to the concept of validation by requiring the bend (to be produced by stroking) to be beyond human strength.
A recent example is the distortion of bowls of tablespoons. Plate 3.1 illustrates examples produced by Julie Knowles; some of them were observed and some not. I needed to know whether both orthogonal radii of curvature of the spoons-lengthwise and crosswise were changed by Julie’s action, and I therefore measured them before and after the operation; I found considerable changes in both. In consultation with metalwork craftsmen I have investigated how such effects could be produced by normal manual force, and have reached the conclusion that there must have been paranormal softening.
Of course it is not unknown for a child to exert more manual force than he should do. I have devised a rather wicked test for such behaviour. I offer a piece of a special metal which, although in appearance soft and elastic, is in fact brittle and cannot be bent quickly without a precisely monitored dynamic force. If the metal-bender attempts to use force, then there is an extremely strong probability he will break the specimen.(16). Although this tactic has been kept secret for a long time, nearly all the metal-bending children have failed to break the brittle specimens I have offered them.
The normal loading of a metal strip causes an elastic deformation proportional to the load, but beyond a certain ‘yield point’, any further deformation which takes place is plastic or permanent in character. The strip work-hardens as it deforms, so that its resistance to deformation increases with time until it is sufficiently large to resist the loading entirely; no further deformation then occurs. But if the resistance is insufficient to resist the loading, fracture then takes place. There are brittle metals and alloys in which the work-hardening is so slight that uncontrolled plastic deformation terminates in fracture. Such metals will not bend plastically, except by ‘creep’, a process which is appreciable only at temperatures greater than one-half of the absolute melting temperature. Thus low-melting point brittle alloys may be deformed by creep at room temperature, but cannot otherwise be deformed plastically just by the imposition of a load. An attempt to cause plastic deformation of a brittle material must involve a load which increases steadily with increasing time. Since it is virtually impossible to terminate a manual load suddenly during the very brief period when the metal is being plastically deformed, it will be impossible to bend manually a suitably chosen specimen of brittle material, except in a long period of time during which creep occurs.
Creep is the deformation produced very slowly by the continuous application of a load. The rate at which deformation occurs is not constant; according to Andrade’s law, the deformation is proportional to the cube root of the time for which the load is applied. Although the law is an incomplete description, it applies reasonably well to the eutectic alloy of bismuth, tin and cadmium (54% Bi, 26% Sn, 20% Cd) (m.p. 103°C). At room temperature the loading of a 6 mm X 8 mm specimen, supported by two knife-edges 10 cm apart, with a 3.2 kg load for 4.25 hr. produces a bend through l6°. A sudden application of 3.5 kg under the same conditions fractures the specimen.
A suitably dimensioned specimen of this alloy cannot be bent by normal force through a large angle in a time of the order of minutes. When it is normally fractured there is often the appearance of a bend at the break. Even in boiling water the alloy is still brittle and fracture will occur. In order to produce normally a large angle bend without fracture, a machine producing a time-varying strain would have to be constructed.
A specimen of this alloy can be used for testing a metal-bender without concentrated observation, since the continuous application of surreptitious force will almost inevitably cause fracture. However, these tests have not deterred the children. Specimens 15 cm in length and 6 X 8 mm in cross-section have been bent without fracture by Andrew G. and Nicholas Williams as follows: 135° in l0 min. l00° in 5 min. 67° in 3 min. 62° in 2 min. 40° in 10 min. and 34° in 6 min. At one session Nicholas W. placed four specimens in his coat pocket, and within five minutes all four had been bent through angles 111°, 135°, 160° and 170°. As with bends that have been produced by creep loading for much longer periods, there was very little work-hardening, as can be seen from the data in Figure 3.1. The action must have been paranormal.
The bending of valuable items of porcelain in the private collection of a Swedish woman, recently investigated by Professor Hans Bender and Dr Hans Betz, fall into the category of paranormal bending of brittle material.
Another validation experiment which involves a task beyond human powers is the rupture of epoxy-resin bonds made to thin strips of metal. In the early experiments I had bonded pieces of different metals together in order to see which bent the most when exposed to subjects; but usually the resin bond fractured. I therefore obtained from Mr K.F. Thompson of Ciba-Geigy (makers of Araldite) a large number of tested epoxy-resin bonds of pairs of thin aluminium strips, each 1 inch wide. I then exposed these to the stroking action of child metal-benders. Although some strips merely bent, a significant proportion of the bonds fractured. The shear strengths (against fracture by pulling) are several thousand Newtons, well beyond human strength. However, the peel strengths are much lower and are within human strength. Therefore only those fractures are genuinely beyond human strength in which the two pieces do not show the distortion that inevitably accompanies a peel fracture of thin strips of metal bonded together. Table 3.1 lists the fractures achieved as of March 1977; the nineteen undistorted fractures must be regarded as paranormal.
Figure 3.2 Two pieces of eutectic alloy of bismuth, tin and cadmium (6 X 9 mm X 15 cm), paranormally bent by Nicholas Williams. Hardness measurements (VPN) on side faces and convex faces.
Another device for avoiding the application of manual force for bending metal strips has been used successfully by Dr Osborne, a physicist who has researched metal-bending children in Australia. A precisely flat metal strip is recessed into a thick bar of clear brittle plastic, being held tightly in the recess at the ends and sides, but not actually stuck with adhesive. The possible elastic bending of the plastic without fracture is arranged so as to be insufficient to cause a permanent bend of the metal strip. Thus any permanent bend must come about as a result of suppression of the elastic properties of the metal; that is, a temporary softening.
Dr Osborne, like Professor Taylor in England, has made use of a spring balance, of the type used for weighing mail, to avoid the use of manual force by a metal-bender. A metal strip is securely attached to the pan of the balance, and the movement of the pointer is watched by the observer while the metal-bender gently strokes the strip. Testing of such a device shows that the application of strong manual bending moment to the strip without causing deflection of the balance pointer is extremely difficult.
‘Homework’ techniques
By far the most difficult type of validation is that of metal-bending unobserved at the time of action. It would be convenient if one could with certainty accept as genuinely paranormal some of the specimens which have been claimed to be paranormally bent by the children in their homes. But this is very difficult to do. One way would be if by good fortune the properties of paranormally bent metal turned out to be obviously different from those of physically bent metal; but we have already seen that this is unusual. Hardness measurements, for example, are often well within the range of normally bent specimens. I have therefore accepted ‘homework tasks’ as evidence of paranormality only when the metal specimens were enclosed within laboratory glassware.
Two of the British metal-bending children produced their most effective work in the privacy of their own bedrooms; one, Andrew G., invented the ‘paperclip scrunch’. Under his action, paperclip wires curled up into all sorts of shapes; they would twist together and tighten up, making decorative forms. Little men and animals began to make their appearance; at first they were formed from only four or five paperclips, but eventually Andrew worked with as many as fifty or a hundred. Some of the most impressive are illustrated in Plate 3.2. The action used to take place quite fast, but failed to occur under visual observation, although audio and magnetic observation (chapter 7) have occasionally been successful.

Obviously it is possible to fabricate paperclip scrunches with the fingers, but in order to determine whether the action was paranormal, I decided to find out whether Andrew could produce them inside glass globes. It turned out that he could do this only when the globe contained a small orifice. Very little success was achieved with completely sealed globes; but when a hole even as small as 2 mm in diameter was allowed, and straightened paperclips were inserted through it, then wonderful scrunches were obtained. Straight metal strips were also inserted; they bent in such a way that they could not be extracted. Two of the twenty-two spheres are illustrated in Plate 3.3.
It is possible, as Society for Psychical Research member Denys Parsons showed, to unravel a scrunch with the use of tweezers, etc., and to extract it through the orifice in the globe. This exercise was carried out on the scrunch in sphere P. and it showed that the scrunch was apparently prefabricated in small sections. Of course this does not mean that the scrunch tightening was not paranormal. To cast doubt on Andrew’s scrunches we would need to reproduce similar ones by normal means, using tools. The first such replication was done by David Berglas, but in the opinion of many who saw the result it was not very convincing. Eventually Society for Psychical Research members Richard Alabone and Denys Parsons produced two impressive normal scrunches; but on inspection we found that the wires were not so tightly bound as in Andrew’s scrunches. Also the time taken for fabrication was rather long, and the tightening was carried out on the entire assembly of paperclips. Andrew, on the other hand, could do the operation in stages, taking only a few minutes per stage; two of his scrunch histories were recorded photographically and the photographic history of one of these appears in Plate 3.4. In my opinion the tightening of the paperclips within the globe is possible in these short periods of time only when some paranormal distortion takes place; equally rapid achievement of really strong tightening by normal means using tools has not been achieved.
The globes have been widely exhibited and inspected and have impressed many people with the reality of unobserved paranormal metal-bending. However, it has been argued by others that the validation of unobserved phenomena by this technique is not watertight, and I did not pursue the work beyond this stage.
Plate 3.3 Scrunches within glass spheres produced by Andrew G.
Sphere Q. made of unusually thin glass, diameter 127 mm, orifice diameter 3 mm. Scrunch of eight paperclips made in four stages of 23 minutes, 5 minutes, 10 minutes, and inspected after each stage by the family.
Sphere S. diameter 132 mm, orifice diameter 8 mm. Made in nine stages of a few minutes each, and photographed by the author after each stage.
Plate 3.4 Serial history of fabrication of scrunch T within sphere of diameter 132 mm, orifice diameter 8.5 mm. Successive stages of eight paperclips in 9 min. five in 7, six in 7; eight in 8, five in 13, five in 11; three + eight in 7 + 6, six in 9, six in 15; five in 10, and six in 6 min.
Stronger testimony now exists in the shape of metal pieces bent inside hermetically sealed glass tubes. These bends are small and undramatic, but there is no doubt that they have been obtained.
I first recorded such a bend in a 3 cm length of 3 mm X 0.5 mm annealed alpha-brass offered to Belinda H. The flatness was within 0.l mm before sealing, and after extraction a deformation of about 0.6 mm, together with some twisting, was recorded. More recently Mark Henry has bent for me a piece of alpha-brass 7.6 cm X 1 cm X 0.77 mm sealed inside a plastic tube with epoxy-resin seals at each end by Dr Brian Millar. The deformation was 1.55 ± 0.04 mm; since there had been no annealing, I heated the deformed strip to 350°C, but the deformation, although reduced, still remained permanent. I experimented to see whether such deformations could be produced by prolonged violent shaking of the tube, and found that they could not.
Dr Crussard and Dr Bouvaist of the Pechiney Aluminium Company in France (chapter 13) have also reported the bending of metal inside hermetically sealed laboratory glassware by metal-bender JeanPierre Girard. Only 0.5 per cent strain was recorded-comparable with the small bends obtained by Belinda H. and Mark Henry.
Plate 3.5 Metal items (nail, spring and brass strip) bent by JeanPierre Girard within glass tubes sealed by Dr Wolkowski
Dr Wolkowski, who conducted the first experiments with Jean-Pierre Girard in Paris, has also reported unobserved bending within sealed tubes. Three of his sealed tube experiments resulted in more dramatic bends, which are illustrated in Plate 3.5. What is different about these glass tubes is that the sealing is not hermetic; they would probably not hold a good vacuum, since the glass at one end was softened and pinched together by Dr Wolkowski rather than drawn out in a single thread under rotation. However, since such bends could not be produced by the operation of tools through these very small vacuum leaks, the validation is good.
Dr Wolkowski writes:(21)
We then embarked on a more sophisticated experiment, which consisted of sealing different metal objects in Pyrex glass tubes; these were completely sealed with a torch. They were weighed with a precision of g and measured with a precision of m, and were left with Girard. inside we had placed different metal objects such as metal paperclips and steel springs of the coil kind; when they were returned to us they were quite remarkably bent, from 10° to 30°. The steel spring, for example, which was straight at the beginning, was now so distended that at one point it could no longer move freely in the Pyrex tube. All the tubes were still the same weights and the same dimensions, and the glass blower could not detect any tampering.