By using the Zapruder, Nix and Muchmore motion pictures, the President's location at the time the bullet penetrated his head was fixed with reasonable precision. A careful analysis of the Nix and Muchmore films led to fixing the exact location of these cameramen. The point of impact of the bullet on the President's head was apparent in all of the movies. At that point in the Nix film a straight line was plotted from the camera position to a fixed point in the background and the President's location along this line was marked on a plat map.327 A similar process was followed with the Muchmore film. The President's location on the plat map was identical to that determined from the Nix film.328 The President's location, established through the Nix and Muchmore films, was confirmed by comparing his position on the Zapruder film. This location had hitherto only been approximated, since there were no landmarks in the background of the Zapruder frame for alinement purposes other than a portion of a painted line on the curb.329 Through these procedures, it was determined that President Kennedy was shot in the head when he was 230.8 feet from a point on the west curbline on Houston Street where it intersected with Elm Street.330 The President was 265.3 feet from the rifle in the sixth-floor window and at that position the approximate angle of declination was 15°21'.331

NUMBER OF SHOTS

The consensus among the witnesses at the scene was that three shots were fired.332 However, some heard only two shots,333 while others testified that they heard four and perhaps as many as five or six shots.334 The difficulty of accurate perception of the sound of gunshots required careful scrutiny of all of this testimony regarding the number of shots. The firing of a bullet causes a number of noises: the muzzle blast, caused by the smashing of the hot gases which propel the bullet into the relatively stable air at the gun's muzzle; the noise of the bullet, caused by the shock wave built up ahead of the bullet's nose as it travels through the air; and the noise caused by the impact of the bullet on its target.335 Each noise can be quite sharp and may be perceived as a separate shot. The tall buildings in the area might have further distorted the sound.

The physical and other evidence examined by the Commission compels the conclusion that at least two shots were fired. As discussed previously, the nearly whole bullet discovered at Parkland Hospital and the two larger fragments found in the Presidential automobile, which were identified as coming from the assassination rifle, came from at least two separate bullets and possibly from three.336 The most convincing evidence relating to the number of shots was provided by the presence on the sixth floor of three spent cartridges which were demonstrated to have been fired by the same rifle that fired the bullets which caused the wounds. It is possible that the assassin carried an empty shell in the rifle and fired only two shots, with the witnesses hearing multiple noises made by the same shot. Soon after the three