Mary Roach - Stiff

MacPherson’s theory would explain the difficulties the army had in La Garde’s day with the Moro tribesmen, who presumably weren’t familiar with the effects of rifles and kept on doing their Moro tribesman thing until they couldn’t—owing to blood loss and consequent loss of consciousness—do it anymore. Sometimes it isn’t just ignorance as to what bullets do that renders a foe temporarily impervious. It can also be viciousness and sheer determination. “A lot of guys take pride in their imperviousness to pain,” MacPherson said. “They can get a lot of holes in them before they go down. I know an LAPD detective who got shot through the heart with a .357 Magnum and he killed the guy that shot him before he collapsed.”

Not everyone agrees with the psychological theory. There are those who feel that some sort of neural overload takes place when a bullet hits. I communicated with a neurologist/avid handgunner/reserve deputy sheriff in Victoria, Texas, named Dennis Tobin, who has a theory about this. Tobin, who wrote the chapter “A Neurologist’s View of ‘Stopping Power’” in the book Handgun Stopping Power , posits that an area of the brain stem called the reticular activating system (RAS) is responsible for the sudden collapse. The RAS can be affected by impulses arising from massive pain sensations in the viscera. [23] MacPherson counters that bullet wounds are rarely, at the outset, painful. Research by eighteenth-century scientist/philosopher Albrecht von Haller suggests that it depends on what the bullet hits. Experimenting on live dogs, cats, rabbits, and other small unfortunates, Haller systematically catalogued the viscera according to whether or not they register pain. By his reckoning, the stomach, intestines, bladder, ureter, vagina, womb, and heart do, whereas the lungs, liver, spleen, and kidneys “have very little sensation, seeing I have irritated them, thrust a knife into them, and cut them to pieces without the animals’ seeming to feel any pain.” Haller admitted that the work suffered certain methodological shortcomings, most notably that, as he put it, “an animal whose thorax is opened is in such violent torture that it is hard to distinguish the effect of an additional slight irritation.” Upon receiving these impulses, the RAS sends out a signal that weakens certain leg muscles, with the result that the person drops to the ground.

Somewhat shaky support for Tobin’s neurological theory can be found in animal studies. Deer may keep going, but dogs and pigs seem to react as humans do. The phenomenon was remarked upon in military medical circles as far back as 1893. A wound ballistics experimenter by the name of Griffith, while going about his business documenting the effects of a Krag-Jorgensen rifle upon the viscera of live dogs at two hundred yards, noted that the animals, when shot in the abdomen, “died as promptly as though they had been electrocuted.” Griffith found this odd, given that, as he pointed out in the Transactions of the First Pan-American Medical Congress , “no vital part was hit which might account for the instantaneous death of the animals.” (In fact, the dogs were probably not as promptly dead as Griffith believed. More likely, they had simply collapsed and looked, from two hundred yards, like dead dogs. And by the time Griffith had walked the two hundred yards to get to them, they were in fact dead dogs, having expired from blood loss.)

In 1988, a Swedish neurophysiologist named A. M. Göransson, then of Lund University, took it upon himself to investigate the conundrum. Like Tobin, Göransson figured that something about the bullet’s impact was causing a massive overload to the central nervous system. And so, perhaps unaware of the similarities between the human brain and that of Jersey cows at six months, he wired the brains of nine anesthetized pigs to an EEG machine, one at a time, and shot them in the hindquarters.

Göransson reports having used a “high-energy missile” for the task, which is less drastic than it suggests. What it suggests is that Dr. Göransson got into his car, drove some distance from his laboratory, and launched the Swedish equivalent of Tomahawk missiles at the hapless swine, but in fact, I am told, the term simply means a small, fast-moving bullet.

Instantly upon being hit, all but three of the pigs showed significantly flattened EEGs, the amplitude in some cases having dropped by as much as 50 percent. As the pigs had already been stopped in their tracks by the anesthesia, it is impossible to say whether they would have been rendered so by the shots, and Göransson opted not to speculate. And if they had lost consciousness, Göransson had no way of knowing what the mechanism was. To the deep chagrin of pigs the world over, he encouraged further study.

Proponents of the neural overload theory point to the “temporary stretch cavity” as the source of the effect. All bullets, upon entry into the human form, blow open a cavity in the tissue around them. This cavity shuts back up almost immediately, but in that fraction of a second that it is agape, the nervous system, they believe, issues a Mayday blast—enough of one, it seems, to overload the circuits and cause the whole system to hang a Gone Fishing sign on the door.

These same proponents believe that bullets that create sizable stretch cavities are thus more likely to deliver the necessary shock to achieve the vaunted ballistics goal of “good stopping power.” If this is true, then in order to gauge a bullet’s stopping power, one needs to be able to view the stretch cavity as it opens up. That is why the good Lord, working in tandem with the Kind & Knox gelatin company, invented human tissue simulant.

I am about to fire a bullet into the closest approximation of a human thigh outside of a human thigh: a six-by-six-by-eighteen-inch block of ballistic gelatin. Ballistic gelatin is essentially a tweaked version of Knox dessert gelatin. It is denser than dessert gelatin, having been formulated to match the average density of human tissue, is less colorful, and, lacking sugar, is even less likely to please dinner guests. Its advantage over a cadaver thigh is that it affords a stop-action view of the temporary stretch cavity. Unlike real tissue, human tissue simulant doesn’t snap back: The cavity remains, allowing ballistics types to judge, and preserve a record of, a bullet’s performance. Plus, you don’t need to autopsy a block of human tissue simulant; because it’s clear, you just walk up to it after you’ve shot it and take a look at the damage. Following which, you can take it home, eat it, and enjoy stronger, healthier nails in thirty days.

Like other gelatin products, ballistic gelatin is made from processed cow bone chips and “freshly chopped” pig hide. [24] According to the Kind & Knox Web site, other products made with cow-bone-and-pigskin-based gelatin include marshmallows, nougat-type candy bar fillings, liquorice, Gummi Bears, caramels, sports drinks, butter, ice cream, vitamin gel caps, suppositories, and that distasteful whitish peel on the outside of salamis. What I am getting at here is that if you’re going to worry about mad cow disease, you probably have more to worry about than you thought. And that if there’s any danger, which I like to think there isn’t, we’re all doomed, so relax and have another Snickers. The Kind & Knox Web site does not include human tissue simulant on its list of technical gelatin applications, which rather surprised me, as did the failure of a Knox public relations woman to return my calls. You would think that a company that felt comfortable extolling the virtues of Number 1 Pigskin Grease on its Web site (“It is a very clean material”; “Available in tanker trucks or railcars”) would be okay with talking about ballistic gelatin, but apparently I’ve got truckloads or railcars to learn about gelatin PR.