Chapter 9
The localisation of metal-bending action


We now address ourselves to the problem; how local is the paranormal action on metal? Obviously this is related to the problems of strain profile distribution (chapter 6) and also to the problem of distance effects (chapter 8).
The localization along a metal strip is partly defined by the width of the Gaussian curves of the last chapter, but this is of course an incomplete definition; the resolution of the experiment is limited by the distance between adjacent strain gauges, normally several centimetres. It might be that the action varies in strength, from millimetre to millimetre, or is even more localized. As will be discussed below, l have recently had the opportunity to conduct experiments with the miniaturized strain gauges now available; but at first I could rely only on less direct evidence.
In chapter 5 I suggested the model of a 'surface of action', a surface or perhaps a laminar region in which all paranormal metal-bending action takes place. If one imagined such a surface to be flat or gently curved, one might suppose that the forces were not at all local, but extended over a reasonably large area. Indeed, at an early stage in the investigations, I was introduced not only to the smoothly curving artwork of Andrew G., but to accurately formed parabolas as much as 30 cm long; these first appeared among the bends produced by David Nemeth; Julie Knowles and Andrew G. were also able to produce large arcs of parabolas, hyperbolas and even exact circles. But Nicholas Williams found it difficult to produce gentle and regular curvature. Many of Willie G.'s smooth parabolas were 'abnormal plane bends' in aluminium strip of cross-section 0.75 X 6.5 mm; they are in the plane of the long dimension, not (as would be expected) in the plane of the short dimension. To produce such smooth bends in this plane is quite a difficult operation when achieved by normal means, for example by means of a conical roller on a flat plate.
A normal parabolic bend is produced not by force applied at a single point between two supporting points (three-point load) but by a force uniform along the bent portion; this action would be produced over the central part of the specimen by a four-point load. It was the uniformity of the parabola bends which interested me in the first instance. I believed that my early observations favoured smooth and initially planar surfaces of action without strong localization. Possibly the long parabolic bends might have been produced by a uniform distribution of individual strain pulses. But just how local is it possible for the action to get? I undertook a number of experiments to throw light on this question. I offered Andrew G. metal strips scaled to different sizes, in order to see whether he could produce without touch similar objects of different dimensions; what would be the upper, and more particularly the lower limit to Andrew's paranormal craftsmanship? l found that the smallest scale objects, involving curvatures of about 1 mm diameter, were not of the same high standard as the others. Thus 1 mm diameter curved surfaces of action were not easily controlled by Andrew. This is consistent with his failure to make tight twists with the thinnest metal strips (chapter 7).
In another experiment I attached a number of resistive strain gauges close together on a circular piece of metal, in order to see whether paranormal signals were registered on neighbouring gauges. I have in one such session with Mark Henry obtained more than fifty signals without a single synchronism between any two strain gauges. The strain gauges were arranged on a circular disc radially with their inner edges on a circle of radius 8 mm. The experiment was designed for the investigation of directional effects, and other similar sessions are discussed in chapter 10. But since no synchronous signals were obtained, the only conclusion possible was that in this particular session (observed by Professor Barzilai of the University of Rome) Mark's action was all localized on individual strain gauges. The metal disc did not bend visibly.
There is some evidence that in certain signals the paranormal action is localized on the strain gauge rather than on the metal. On several occasions towards the end of sessions a strain gauge has suddenly become open-circuit, although there had of course been no touching. I always examined the open-circuit strain gauge under magnification, and found unexplained damage which I eventually attributed to strong localized paranormal action. A magnified photograph of a damaged strain gauge sensor appears in Plate 9.1b, contrasted with an undamaged strain gauge in Plate 9.1a. It is also possible that resistive strain gauge signals showing 'tails' (e.g. in Figure 4.4b) are indicative of localized action on the strain gauge. The gauges are affixed to a prepared metal surface with one of a number of recommended adhesives. The polymer film on which the resistive film is deposited does not necessarily expand and contract at the same time or rate as the metal to which it is affixed. If the paranormal action is on the metal alone, or simultaneously on the strain gauge and on the metal, the expansion and contraction will be simultaneous. There is no tail on such a signal. But if the action is localized on the resistive strain gauge, then a mechanical relaxation, of long time-constant, in the adhesive film could influence the motion of the gauge. The time-constants for these 'tails' are of the order of 1 to 5 seconds; a thermal time constant interpretation is ruled out because compensation of the strain gauges ensures that it would require a temperature change of at least 10°. When employing temperature sensors (chapter 14) we have never found such temperature changes on a paranormally bent metal specimen. Nevertheless the physical origin of tails on signals is not unambiguously decided, and further experimentation is necessary. Tails cannot be avoided by embedding the sensor in epoxy-resin within the metal.
Plate 9.1 Comparison between (a) an unused and (b) a paranormally damaged strain gauge sensor. Overall length of the plastic mounting, 9 mm. The damage to the strain gauge is not to the solder tags, which are soldered in blobs, but to two of the filaments, which appear to be cut diagonally; some others show signs of incipient damage.
Figure 9.1 Localization of dynamic strain signals on miniaturised strain gauges, whose dimensions can be seen from the scale drawing at the top. A family of Gaussians is drawn and their localization parameters L are calculated. The localization parameters from the strain gauge session are sorted into groups according to magnitudes corresponding to the Gaussian L values. An (inverted) histogram of the strain gauge L values is shown.
Mattuck and Scott Hill,(25) like ourselves, have drawn attention to the possibility that localized paranormal action might loosen the strain gauge from the surface of the metal. In an experiment with Girard, they observed an anomalous stretching signal on a gauge attached to the concave side of a deformed bar. The 'strain gauge slip' was confirmed by a subsequent normal deformation experiment on the identical specimen, which demonstrated the failure of the strain gauge to follow the normal deformation.
I have now been able to study localization with Stephen North using five closely spaced miniature strain gauges whose working length is each about one millimetre. Wide distributions of magnitudes of signals, and even changes of sense between one strain gauge and the next, were found.
These have been found by fitting to a trigonometric series
I=A +Bx + C1 sin x + C2 sin 2x + C3 sin 3x + . . .
The ratio L = |C3|/|C2| can be considered as a possible quantitative measure of localization of each signal quintet, and the value of L is compared to values calculated for Gaussian curves; Figure 9.1 shows that the action can be said to be localized to distances of the order of 4 mm.

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