FOUR MEN BANGING ON A WALL
John Junot has proposed an imaginative explanation for the Bundy murders: "Kato did it." He arrives at this by doubting some of the indications in the evidence, and then creating an explanation to resolve that doubt. One of his sources of doubt is the five-drop blood trail, which he believes is inconsistent with the Bruno Magli footprints, and I have addressed that question here recently. There is no inconsistency.
But, the centerpiece for his theory is an experiment that he mentions that was done by the defense investigators when they visited the Rockingham scene on June 26. Junot says that four men tried to recreate the event Kato described (the "three thumps") by pounding on the outside of his wall to dislodge and "move" the painting on the inside of his wall as Kato
claimed happened at abut 10:45 on the night of the incident. These experiments did not move the painting, and Junot believes this is an indication that the event Kato described did not actually happen.
THE EXPERIMENT: The sketchy description of the defense experiment is found on p. 145 of Schiller's "American Tragedy." Several men visited Simpson's Rockingham estate, examined Kato's room, and identified a painting on the south wall. At that time, I presume that the painting was hanging straight, as I also presume it was on the night of the incident. Then, a couple of the men walked around the house to the outside of the wall and threw themselves against it and pounded on it with their fists, while the men remaining in Kato's room watched the painting and saw that it did not move. After several tries, there was still no movement in the painting.
A HANGING PAINTING: Consider now the way in which a painting is commonly hung on a wall. A picture hook is fastened to the wall (or a nail is simply driven halfway into it.) A slack wire is fastened to the back of the painting from about the middle of the left side of the frame to the middle of the right side. A person holds the painting facing himself, and places it against the wall, then moves the painting up and down until he can feel the wire catch on the hook. He lets the painting down until its weight is supported by the hook, straightens it, and lets go. Sometimes it will fall out of straight when it is let go, and some further adjustment is necessary, but eventually by trial and error a condition will be achieved whereby the painting is straight without being further touched. The painting is "hung."
Now consider the relationship between the wire and the hook when the painting is hung. The wire is in the form of an inverted V with the hook at the apex. Ideally, the figure is symmetrical; that is, the length of the two legs of the V is the same, and the angles down from the apex are the same. When this happens, the painting is hung in a "stable" mode. In this mode, the picture will not only remain straight when released, but will resist efforts to move it out of straight, and will tend to resume a straight condition if displaced.
But, because this arrangement of wire and hook is behind the painting, it is concealed from the picture hanger, and he can not see directly whether that ideal has been achieved. It often happens that on the first try the picture is hung "off center," that is, it is hung so that one leg of the V is longer than the other, and the angles at the apex are substantially unequal. Because of this, it can happen that when the picture is released, it will fall out of straight. Such a condition is "unstable," and can not be corrected by simply straightening the painting; it will again fall into a cocked orientation when released. It is necessary to take the weight off the painting, shift it left and right to find a new position for the wire/hook engagement, and try to straighten and release it again. By trial and error, a condition will be found where the picture will remain straight when released.
However, it can also happen that the painting will remain straight when released, but the concealed wire/hook relationship contains a small dissymmetry in the angles of the wire. This is the "metastable" condition. A picture hanging in this way has a natural tendency to hang in a cocked orientation, but that tendency is not sufficient to overcome the friction of the painting against the wall, and so it stays in the straight orientation in which it was put. However, if subject to some mechanical vibration, a metastable picture will spontaneously move to the skewed orientation that is natural for it.
EXPLAINING THE EXPERIMENT: Now that the nature of hanging pictures is understood, it is rather obvious what happened in the case of Kato's picture. Kato says that there was a loud sound as though someone was pounding on the outside of his wall, and during that the picture moved. Thereby, we now understand that the picture was hanging in the metastable mode before the pounding, and that the action caused the picture to rotate to it's natural (cocked) position. The natural fate for a crooked picture is that someone will come along and straighten it, and I presume that happened to this one (however, see below). The person who straightened it could restore it to its original metastable condition, or could put it in a stable condition.
But, later the four men came along and did their experiment. The picture in that case did not move, so we know that its condition when they started was that it was in the stable condition. That is, if the picture was straightened after Kato's experience, it was also made to hang stable. However, it is also possible that when the men arrived to do their experiment the picture had not been straightened, but was hanging as Kato saw it after the pounding, that is, crooked. Now, a straight but metastable picture that is shaken into a cocked orientation is then stable but crooked. So, after Kato's experience, the picture was stable. If it was still in this condition when the men arrived to do the experiment, it would also not be shaken into some other orientation by their pounding.
Therefore, we understand that the result of the four men pounding on the wall is simply explained by the mechanics of hanging pictures. There is no reason to disbelieve that Kato actually had the experience he did, and also that the four men were not able to recreate that experience. It is all explained by the way in which the picture was hanging, and no one made a distinct observation of that.
Dick Wagner Van Nuys, CA (1/24/99) NG_508