Z-308 and 312

[Gerry Hemming]

The slight head movement occurs between 312 and 313. Josiah Thompson, the first one to note the movement, I believe, now says he believes there was no such movement. He attributes the perceived movement to the blur of the film.

Josiah Thompson also believes that David Wimp's deceleration theory has merit. Contributing to that theory is the fact of JFK's back brace. Given that his torso was held upright by a back brace, the president's head was more prone to reflect the deceleration than other occupants of the limo, who would have shown the effects in a more generalized fashion.

Fetzer claims I want to return things to their 1967 basis. This, of course, is nonsense. Let me rebut it by pointing out a major mistake I made in "Six Seconds." I measured there that JFK's head moved forward about two inches between Z312 and Z313. This forward movement followed by the obvious left, backward snap suggested to me that he had been hit in the head from the rear and then, almost instantaneously, from the right front. Within the last few years, Art Snyder of the Stanford Linear Accelerator Laboratory, was able to show me how this involved a serious mistake in measurement. As you all know, Z312 is quite clear while Z313 is smeared from movement of the camera. Using fairly complicated math, Snyder was able to demonstrate to me that I was measuring the smear on frame Z313 and not the movement of Kennedy's head. That socalled "two-inch movement" was an illusion; it came from the smear.

David Wimp and Joe Durnavich came to much the same conclusion. Wimp, however, has gone futher. He has shown that JFK's head begins moving forward about Z308 and that everyone else in the limousine... Kellerman, Greer, Jackie, Mrs. Connally, John Connally... also begin a moderate movement forward at that time. After Z314, JFK flips backward and to the left while all the rest continue moving forward. The explanation: When Greer turned to look in the back seat at circa Z302 his foot tapped the brake, decelerating the limousine and throwing forward all the limousine's occupants. There is no longer any clear evidence in the Zapruder film of Kennedy being hit in the back of the head. (I say "clear" because there may be some evidence of a hit from the rear at Z327/328) The Z312-Z317 sequence... the bowling over of JFK to the left rear.... is the unambiguous result of a shot from the right front.

This is wonderful progress by careful research.

Tim Carroll

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I wore a similar type "girdle" back-brace after a parachute failure [total malfunction - 1965]. It is an over the shoulder vest type which rubs against the back of the neck. Just where is that "girdle" with the "hole in the shoulder blade" area stored today ??!!

GPH

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[Ron Ecker]

Gerry,

The back brace that JFK wore did not extend up his back. Here's a link where there's a picture of him wearing it, while talking with Earl Smith. I think it's also pictured in a WC exhibit.

http://images.google.com/imgres?imgurl=htt...6lr%3D%26sa%3DG