Atlatl and Dart

So you’re hungry, and you want meat, and it’s thirteen thousand years ago in North America. There are no firearms, no guns, no steel knives. How are you going to hunt something to eat? And you want something big enough for everyone in your band to eat – a rabbit won’t do. You want something big, and, therefore strong, and fierce and fearless.

Well, you think you’ve got four options: Spear; javelin; bow and arrow; atlatl and dart. But, you’re wrong, so sorry: The bow and arrow haven’t been invented yet; haven’t come into use in North America yet. So that leaves three options:

You could use a spear. A spear is a handheld thrusting device, made of a wooden shaft, tipped with a very sharp knapped point. Very nice, but of course, you’ve got to get right up next to whatever it is you’re trying to kill, and believe me, right about now, what ever it is you’re trying to kill, is trying to kill you right back.

You could hunt with a javelin. A javelin is similar to a spear, but lighter, and thrown by hand. But these big animals – the mammoths, the mastodons, all have really thick hide, and fur over that. You can wound them, maybe, irritate them, but they’ll just run off, or worse, charge you. You just don’t have the strength, the speed, the leverage to throw a javelin hard enough to really be effective.

Or you could use a dart, flung from an atlatl.

A dart? An atlatl? Huh?

Read on, dear reader, and learn more about the atlatl, and how it changed the world.

The term ‘atlatl’ has come, in recent years to be used in lieu of the former term ‘spear-thrower.” “Atlatl” itself is word from the Nahuatl language (Aztec). But whatever term is used to describe it, the atlatl is an ingenious and effective invention. It’s based on the principle of leverage. In much the same way that a lacrosse player, using his or her stick, can throw a lacrosse ball much faster and farther than by merely using his arm, an atlatl let a hunter hurl a dart much faster, farther and with much more force than by throwing a javelin.

Are you familiar with those plastic molded tennis ball throwers that you use to throw a ball for a dog? That is very similar to an atlatl, in the sense that it lengthens the arc through which the tennis ball travels before it is released. As a result, the ball gains velocity, leaves the thrower at a higher rate of speed than if you just threw it with your puny human arm, and therefore travels much faster and farther.

Same thing with an atlatl.

An atlatl is a wooden shaft, with a hook or notch at one end. The operator (you) holds the other end. The butt of a dart is hooked into the hooked end of the atlatl, and then the operator also holds the shaft of the dart, where it lines up with the handle end of the atlatl. Then the operator, you, cocks his (or her) arm back, and while retaining a firm grasp on the handle of the atlatl, releases the grip on the dart. As the arm moves forward, the momentum of the throw is transferred from the thrower’s arm to the atlatl, down the shaft of the atlatl to the butt end of the dart, and thus, the dart is propelled in a larger arc, than the arm alone could give.

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[1]

Darts were designed for use with atlatl. They are thinner, and lighter than handheld spears, and they can be long – five to seven feet in length, maybe more. They look like gigantic skinny arrows: A point at one end, and feather fletching at the other. The shaft bends and flexes in flight, and the fletching helps the dart fly true.

And it really works. The atlatl can propel the dart at speeds up to 100 mph.

It’s not intuitive – it takes skill and practice. But when used by a capable operator, it gave hunters a tremendous advantage: The atlatl lets a dart be thrown much faster, much harder, and much farther than a javelin. And, for that matter, a dart thrown from an atlatl is a more effective hunting tool than an arrow in each of three measures: “how hard it hits (kinetic energy), how hard it is to stop (momentum), and how effectively it penetrates (sectional density).”[2] According to one study, Hrdlicka, D. “How Hard Does It Hit? A Revised Study of Atlatl and Dart Ballistics,” The Atlatl, Vol. 16, No. 2, 2002, a dart beats an arrow in each of these three categories. His calculations are beyond the scope of this note, but his conclusions are worth noting:

When an object is in motion, it has kinetic energy. When it strikes something, that energy is transferred. This is the basic force of impact – how hard the weapon strikes the target. . . . Kinetic energy is very dependent on velocity. A bullet, because it is moving so fast, has incredible amounts. A .30-06 has roughly 60 times the kinetic energy of a primitive arrow. And yet Native Americans used those primitive arrows to hunt not only deer, but bison as well. . . [B]oth the light dart and the heavy dart seem weak compared to firearms, but they have more kinetic energy than arrows. . . . . . [T]hey would be sufficient to bring down even the toughest game — assuming it is in the effective range. For an atlatl, the effective range is perhaps 50 yards . . .

While kinetic energy determines how hard an object strikes, it doesn’t determine how far it penetrates. That’s where momentum comes in. . . . Momentum is the tendency of an object in motion to STAY in motion. Anyone who has pushed a car in neutral and then tried to stop it will understand this — the more momentum it has, the more resistance it will take to stop it.. . . Projectiles with a lower momentum, like the arrows, may have trouble penetrating thick hide and can be stopped fairly easily if they hit bone. Projectiles with a lot of momentum, like the spears, will go through hide, flesh, bone, and organs, penetrating until they encounter enough resistance to stop them. More momentum also means the projectile is less likely to be deflected by branches or underbrush, so it can be used in different types of terrain.

In addition, momentum is a factor in “knockdown”. A heavy atlatl dart has enough momentum to knock a 40 pound animal completely off its feet and will definitely affect a larger animal. Objects with less momentum, like the arrows or the .357 magnum, will have a much smaller effect. . . . Darts are much more effective in terms of momentum, even better than the .357 magnum. Mass and velocity are equally important in momentum, and darts have quite a bit of mass. It would take more resistance to stop them, which means they would be more effective at penetrating deeply enough into the target to hit a vital area.

Momentum alone isn’t enough for calculating penetration . . . A Ping-Pong ball thrown at a pop can will bounce off. A BB will go right through. What makes the difference? The sectional density. Even though they may weigh the same, in a BB the weight is much more concentrated. Since it is striking a smaller area on the target, more of the momentum is conserved, and it will penetrate deeper. Other factors being the same, a denser projectile will always penetrate more effectively than a lighter one. . . . Atlatl darts are very effective in terms of sectional density. The weight of the long shaft is concentrated in the small diameter, making them more efficient than either arrows or firearms (even the mighty .30-06). This means that the momentum is conserved better, which means the darts will penetrate better.[3]

Another study noted that a dart thrown properly from an atlatl carries more than four times the kinetic energy of a “modern arrow fired from an efficient modern compound bow” (emphasis added).[4] It is worth noting that the use of the atlatl persisted in many places, even after the invention of the bow and arrow. For example, “in his account of the Desoto expedition to the Southeastern United States in the 16th century Garcilaso de la Vega noted that the spearthrower propelled darts ‘with extreme force, so that it has been known to pass through a man armed with a coat of mail.’”[5]

This power and efficiency helps explain why the atlatl was so successful and so widely used.

The range and power advantage provided by the spearthrower . . . , relative to the thrusting-spear or javelin, could have provided Paleoindian hunters with the ability to successfully penetrate the armor-like hides of mammoths . . . greatly increasing a hunter’s chance for success. Likewise, the device’s portability likely permitted Clovis hunters to avoid alternative big game hunting technologies, such as traps or drives coupled with killing lances, thus maintaining a highly mobile subsistence strategy.[6]

An atlatl and dart offered much more power at a greater distance than could be obtained from a javelin. And, of course, hunting from a distance is a benefit for hunters going after large and potentially dangerous game – mastodons, mammoths – since thrusting a spear at an enraged elephant is very dangerous. Don’t try it at home. Don’t try it anywhere.

It may seem counterintuitive that these long darts, flexing through the air toward the prey would be effective hunting tools, but as one author put it,

For tens of thousands of years, it was the primary hunting weapon on earth. Dart points have been found in mammoth bones, and they have been tested on modern elephant carcasses with impressive results. While it may not be as effective as a rifle, it is certainly effective enough. Just how dead do you need your supper?[7]

In fact, darts thrown by atlatls are so effective that it is interesting to speculate about why that technique was largely supplanted by the use of the bow and arrow. I suspect that it may have something to do with the declining size of prey animals. As mammoths and mastodons and the other giant megafauna became extinct, hunters had to turn to smaller, lighter prey, and it may be that the heavy firepower of an atlatl was no longer necessary.

Atlatls have been widely used around the world, in Europe, the circumpolar regions, southeastern Asia, and North America. Atlatls were in use in Europe over 17,000 years ago, and it was long supposed that atlatls came into North America via the Bering land bridge, described earlier. This would mean that the first people known to have inhabited the Americas, the Clovis people, would have been using atlatls.

But no one could say for sure that that was the case. Although atlatl use has been confirmed in North America going back nine or ten thousand years,[8] there has been no definitive evidence that atlatls were used by the Paleo-Indian culture known at the Clovis People. No one has found an atlatl that old. The atlatls that have been found dated from much more recently, even into the 1400’s, and later.[9] “There is no reason to assume that early migrants to the New World could not have possessed the device, but there is currently no empirical evidence that it was actually used by Paleoindian hunters.”[10]

Recently though, in an ingenious bit of science and research, Dr. Karl Hutchings of Thompson Rivers University in Kamloops, British Columbia, Canada has done a study which permits the strong inference that atlatls were used in North America during the time of the Clovis people, earlier than any fossil evidence demonstrates.

How?

Dr. Hutchings studied patterns of lithic fractures on stone points. That is, he studied the micro features of fracture patterns on stone points. His (and others’) prior research had demonstrated that certain fracture patterns are produced by the force which causes the fractures, i.e. how fast and hard the stone point hit a target.

Dr. Hutchings studied 668 stone points and fragments associated with Paleo-Indian cultures. These were mostly fluted[11] points made of chert, flint, quartz, obsidian, jasper, and chalcedony. “The points were recovered from sites and localities on the edge of the Southern Great Plains, the Southwest, and Far West of North America.[12]

So Hutchings is looking at these points, and sees fracture patterns consistent with a high velocity impact. High enough that the point (attached to a javelin) could not have been thrown by hand. As the study noted,

Fracture velocity data derived from the damaged surfaces of North American Paleoindian points  demonstrate that at least some Paleoindian points were subject to much higher loading rates than can be achieved without mechanical assistance. Since North American archaeologists would generally agree that there is no supporting evidence for the use of the bow and arrow during the Paleoindian Period, the spearthrower is, therefore, indicated.[13]

This is a significant, and very smart finding. As the paper notes, there is no evidence that bow and arrow technology was available to the Clovis people at that time – some thirteen thousand years ago. And there is no known alternate mechanism which could have propelled these points at high enough velocity to have produced the pattern of fractures Dr. Hutchings found. Couple this with the fact that the atlatl was known to have been used in Europe and Asia thousands of years before the time period in question, and the conclusion seems eminently reasonable: The first Americans, the Clovis people were hunting animals – big animals – with atlatls.

 

 

 

 

[1] Illustration courtesy of National Park Service and US army, but found at National Geographic News, http://news.nationalgeographic.com/news/bigphotos/7739559.html

[2] Hrdlicka, D. “How Hard Does It Hit? A Revised Study of Atlatl and Dart Ballistics,” The Atlatl, Vol. 16, No. 2, 2002, http://waa.basketmakeratlatl.com/wp-content/uploads/2013/02/HOW-hard-does-it-hit-revised.pdf

[3] Hrdlicka, D. “How Hard Does It Hit? A Revised Study of Atlatl and Dart Ballistics,” The Atlatl, Vol. 16, No. 2, 2002, http://waa.basketmakeratlatl.com/wp-content/uploads/2013/02/HOW-hard-does-it-hit-revised.pdf

[4] Hutchings, W.K., and Bruchert, L.W., “Spearthrower Performance: Ethnographic and Experimental Research,” Antiquity 71 (1997): 890 – 97, 894.

[5] Hutchings, W.K., and Bruchert, L.W., “Spearthrower Performance: Ethnographic and Experimental Research,” supra, 895.

[6]W. Karl Hutchings, “Finding The Paleoindian Spearthrower: Quantitative Evidence For Mechanically-Assisted Propulsion Of Lithic Armatures During The North American Paleoindian Period.” Journal of Archaeological Science 55 (2015) 34-41; Publ. Elsevier, online, Jan. 3, 2015, p. 35.

[7] Hrdlicka, D. “How Hard Does It Hit? A Revised Study of Atlatl and Dart Ballistics,” The Atlatl, Vol. 16, No. 2, 2002, http://waa.basketmakeratlatl.com/wp-content/uploads/2013/02/HOW-hard-does-it-hit-revised.pdf

[8] “The earliest concrete evidence for the use of the spearthrower in the New World is currently represented by the spearthrower hooks from Warm Mineral Springs, and Marmes Rockshelter. The 9000 to 10,000 year old associated dates suggest that the spearthrower was in use by at least the Early Archaic Sub-Period.” Hutchings, supra, p. 35.

[9] See, for example the map showing the distribution of atlatls found in North America.

https://www.google.com/maps/d/viewer?oe=UTF8&ie=UTF8&msa=0&mid=zJJvPeXR_dPY.ktKC0nDyvz80.

[10]“Perhaps more than any other New World culture, the Clovis Paleoindian complex has been popularly defined by a single artifact form; the fluted Clovis point. While there is no doubt that fluted points were used to dispatch late-Pleistocene megafauna . . . the question remains: how were these points used to bring down such large game? [I]t is not known explicitly whether this weapon took the form of a thrust spear, thrown javelin, or mechanically propelled spearthrower dart, since no hafted fluted points have been recovered to date.” Hutchings, “Finding The Paleoindian Spearthrower: Quantitative Evidence For Mechanically-Assisted Propulsion Of Lithic Armatures During The North American Paleoindian Period,” supra, p. 34.

[11] The fluting is diagnostic of Clovis culture, and its successor, Folsom.

[12]Represented sites and localities include Murray Springs, Naco, Dent, Lehner, Lindenmeier, Folsom, Rio Rancho, Blackwater Draw, Sunshine Well, Tonopah Lake, and the Dietz site (interior citations omitted), as well as many lesser known, and unreported sites and localities.” Hutchings, p. 37.

[13]W. Karl Hutchings, “Finding The Paleoindian Spearthrower: Quantitative Evidence For Mechanically-Assisted Propulsion Of Lithic Armatures During The North American Paleoindian Period.” Journal of Archaeological Science 55 (2015) 34-41; Publ. Elsevier, online, Jan. 3, 2015, p. 35.

So – What Happened?

Between 10 and 12,000 years ago, the world changed.  In North America, 35 genera of large mammals became extinct.  Not species, but genera – whole groups of closely related species.  Thirty five genera:  Mammoths, mastodons, giant sloths, horses, saber-toothed cats, the short-faced bear (but not grizzlies), the American lion (but not the Mountain lion), camels (but not llamas and vicunas in South America), the giant beaver, but not the regular little guy.

Bison_herd_grazing_at_the_National_Bison_Range

So – what happened?  Where’d everybody go?  And why?

For years, paleontologists and archeologists have tried to figure this out.  There have been five main theories to explain this wholesale extinction:

  1. Overkill – to much hunting by the newcomers to North America, the so-called Clovis people;
  2. Environmental change;
  3. Disease;
  4. Some extraterrestrial impact, akin to the comet which is believed to have killed the dinosaurs;
  5. Some combination of any of the above.

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One issue that has come up, because of the paucity of fossil remains, and gaps in the fossil record, is the timing of these extinctions.  Did these genera go extinct at roughly the same time, or were these extinctions staggered, spread out over time? Was this a slow catastrophe, or a fast one?

In 2009, two scientists, J. Tyler Faith and Todd Surovell, took a look at this issue, and published an article titled Synchronous Extinction Of North America’s Pleistocene Mammals, in PNAS, vol. 106, no. 49.  No slouchy journal, either – PNAS means Proceedings of the National Academy of Sciences of the United States of America.

By doing a careful statistic analysis of the fossil remains associated with the extinctions, they concluded that “the combination of these lines of evidence suggests that North American late Pleistocene extinctions are best characterized as a synchronous event.”  Specifically, “our analyses demonstrate that the structure of the chronology of North American late Pleistocene extinctions is consistent with the synchronous extinction of all taxa between 12,000 and 10,000 radiocarbon years. B.P.”

Okay, so what does that mean?

It means that most of these animals all became extinct in a two thousand-year span.  The authors note that:

         “Our simulations do not rule out the possibility that some extinctions may have occurred before 12,000 radiocarbon years B.P. The biogeographic simulation suggests that anywhere from 0 to 8 genera could have disappeared before the terminal Pleistocene . . . Even so, 23–31 genera abruptly disappeared at approximately the same time. Our results leave open the possibility for a small level of background extinctions (0–8 genera) followed by a surge in extinction rates that wiped out the remaining taxa (23–31 genera) between 12,000 and 10,000 radiocarbon years B.P.”

So it is possible, they acknowledge, that of the 35 genera that became extinct, maybe as many as 8 of them had gone extinct earlier that 12,000 years ago.  That still means, however, that 27 of them became extinct in that short – remarkably short – period of time.  As the authors put it,

           “Whether or not background extinctions took place, that a catastrophic event or process occurred at the end of the Pleistocene is abundantly clear.”

The implications for this are important.  Whatever happened, it happened very fast, and was continent-wide.  Europe experienced what the authors call a “long-term, piecemeal extinction process.”  Not so, here.  It happened all across the continent, in what they call “a geologic instant.”

BisonBones

This conclusion doesn’t necessarily eliminate any of the five possible causes of the mass extinction, but it does put certain constraints on them.  An environmental change, for example, if it was the primary cause of these extinctions, must have been nation-wide and very rapid.  But intriguingly, even those limits – speed and breadth – still fit with three of the possible causes for the extinctions:  “This time period encompasses the earliest secure evidence of human foragers in North America . . . the Younger Dryas cold interval . . . and a possible extraterrestrial impact.”

Well, science marches on.  We still don’t know why these extinctions occurred.  And while two thousand years may be a geologic instant, in the lives of these animals, it encompassed tens or hundreds of generations.  A drought that lasted five hundred years, or seasons so cold that plants wouldn’t grow, could certainly have caused some of these extinctions.  And there may have been a cascade effect, too:  If a given herbivore becomes extinct or vanishingly rare, then the predator that preys on it is in trouble, too.  And family structures may have been disrupted by hunting, too, for that matter:  If the matriarch of the mammoth herd is killed, maybe the young ones don’t know how to survive a particularly harsh winter, or a dry summer.

But as to what happened?  We still don’t really know.  As Faith and Surovell put it, “further research on the biogeographic histories of individual species in relation to detailed paleoclimatic, paleoecological, and archaeological data could help to finally pin down the cause of North American end-Pleistocene extinctions.”

The Clovis Mission: Ch. 5: Summers

Rain.  Sheets of rain.  Downpour.

 “Ah, shit.”  Lasher spoke. “C’mon, move it!  We gotta get this shit packed up.”   So right away, even before we looked around, the three of us scrambled around and loaded the horses, and saddled the horses, and put on rain clothes, and generally ran around like idiots, until everything was squared away.  Jack was wet, shivering.  And then, of course, the rain stopped.

And I looked around, for the first time, at North America, roughly 12,000 years ago.  You’ve never experienced anything like this.  The air smelled unbelievably fresh and cool.  The sky was clearing and a brisk wind was blowing.  I could see low hills, obscured a little by the mist that was breaking up.  It was cool, morning, early spring.    A couple birds flashed by, but I couldn’t tell what they were.  Bird song – lots of bird song. The country was lightly wooded.  We were still so close to the Mississippi that trees could grow.  The trees were just budding out.  I saw oaks, hickory, a couple willows down in a stream bed near us.

The horses stamped, and a little steam rose from their coats.  Lasher looked around.  We all looked around.  Jack trotted around us, head down, sniffing avidly.  I found I was grinning. Devereaux laughed a little.  Even Lasher smiled.  After a minute or two, Lasher said “All right, let’s get going.”  So we mounted up and set off. 

The first night, we built a small fire, and set up camp for the first time, on a low rise, in a grove of oaks. And started talking. Lasher did, anyway.  He sat there, drinking tea, and asked me, “So, what are we up against?”  I turned.  “What are we likely to encounter out here?” he said.  “I’ve read some about the Pleistocene, but I’d like to hear what you can tell us.  Hey, Devereaux – listen up!”  Devereaux had been futzing around with one of his rifles, but he stopped, and came over to where we were sitting.

“Well,” I said, “that’s really the sixty-four thousand dollar question, isn’t it?  No-one really knows.  I mean, we have fossil evidence of all kinds of animals, most of whom are now extinct  – extinct in our time, that is.  But there’s tons of stuff we don’t know. “

“What kind of animals?”

“Lots.  Lions, bigger than African lions; bison – like superbison – bigger than today’s.  Camels, horses, cheetahs, hyenas, sloths. Saber toothed cats; a giant bear – the short-faced bear – probably the biggest land predator alive in this time.  Mammoths.”

“Jesus Christ,” Devereaux said.  “It’s the American Serengeti.”

“Yeah, and other animals, too. Only, we don’t know nearly enough about them – how many there were; how they lived, how they hunted.  Almost nothing.  That’s one thing Carver was back here studying.”

“Yeah, or why they went extinct.” Lasher said.

“That’s right – we don’t know why that was. “

“Maybe the cavemen wiped them out,” Devereaux said.

“Well, they weren’t really cavemen,” I said. “The people of what we call the Clovis culture were some of the earliest settlers in North America.  We’ve found their stone points, sometimes associated with the skeletons of mammoths.  But again there is still a lot we don’t know.  Where’d they come from?  When?  How?  How did they live?  Where?  How many were there?  This stuff, too, Carver was supposed to be researching.”

“Okay,” Lasher said “Big animals, and lots of ‘em.  How will they react when they see people?  Do we have to worry about ‘lions and tigers and bears oh my?’”

“Yeah, and what about the natives,” Devereaux asked.  “They gonna sneak up on us?”

“Man, I don’t know,” I said. “The people would probably be curious about us, but how that would play out, I don’t know.”

“They better not fuck with us,” Devereaux said.  Christ!  All of a sudden he was a tough guy.

“Look,” I said, “they’re not cavemen.  They’re homo sapiens, just like us.  Modern humans.  As smart as we are, and presumably well adapted to living out here.  We can’t just kill them.”

“No-one’s talking about killing them, right Devereaux?” Lasher said.  “But what about the animals?  Wolf packs, or lions or what have you?”

“I honestly don’t know,” I said.  “This country is so lightly populated that most of the animals, the predators will never have seen people before.  They’d have no reason to fear us.  But we won’t be familiar to them either, so I don’t think they’ll regard us as prey.”

“Yeah,” Lasher said, “but they’re top of the line – apex predators.  They’d have no reason to fear us, right?  But maybe they’re curious.  Or really hungry.  Maybe we look like easy meals to them.  And didn’t you say there were horses here, now?  I’ll bet they’ve seen horses before, and think they’re tasty as hell.”  He stood up.  “So what I think is, we’d better be careful.  I think we’ll take watches, tonight and every night.  Wear the night vision goggles, and keep a sharp eye out. “

That actually seemed like a good idea.  All of a sudden I had visions of packs of huge dire wolves slowly sneaking up and surrounding us.   Just meat for the ravenous.

Nothing happened that night.  We took watches, and it was weird, I can tell you, sitting there, in the absolute darkness, the fire died down to only embers, no ambient light.  The stars looked low, close to the earth, brilliant, like a flung pitcher of milk.  A few clouds, scudding across the sky.  The sliver of the moon rose late. 

I heard coyotes yelping, and then, farther off, wolves. A pack, howling.  That wild and alien sound was haunting.  Jack stiffened, and I thought that he was going to chime in with their chorus. But then I heard the hoarse coughing roar of lion.  A lion!  That’s when I knew, I mean really knew, that we were someplace entirely other, some place and time wholly different from our own.  The horses stamped, restlessly, with some atavistic sense that that wild sound meant danger.  Jack’s ears pricked up, and he growled once, low in his throat.  I called him over, and he flopped down next to me, and I petted him for a while.  Just before dawn, a fox came snooping around the edges of our camp, but our scent was unfamiliar, and it didn’t come into the camp.

Dawn, clear and quite cool.  The sky at first a light, pale blue. The birdsong was loud.    Larks, thrushes, robins. Skeins of geese and other waterfowl, flying north.  Because it was, really, our first day, we celebrated at breakfast with some of the precious store of coffee we had brought with us. 

It didn’t take long to establish our routine, even though there wasn’t, really, any routine, at all.  What I mean is, we’d set out early in the morning, making our way west and a little south, stop briefly at midday, then ride on until evening, when we’d set up our camp.  But there was no routine, really, because of the terrain.  The ground here, in what would later be Missouri and eastern Kansas was rough, wild, unfamiliar.  Deadfalls, streams, rocky outcroppings – everything had to be climbed over or around.  Jack loped around, walking, trotting, sniffing the air, of course, but we kept him close to us – didn’t let him range out in front, the way he had when he’d hiked together back home.  In the mornings, before we mounted up, and at lunch, and then again, in the evenings, I’d work with him, reinforcing our bond, and improving his training.

We passed through the some light woods, and had to stop when a small herd of woods bison came through.  They seemed enormous, dark chocolate-brown, moving sedately, silently past.  Totally unafraid of us.  One bull snorted a little as he passed.  And then gone, like a dream.  Strange that animals that large could move so quietly.  No calves, yet, probably too early in the year.  I grabbed Jack’s collar, out of habit; and then decided to try an experiment.  So I let him go, and simply said “stay.”  And he stayed.  Oh, he looked at the bison as they passed, and sniffed them, and crouched down in that way that border collies have – but he stayed.

After several days of travel, the woods thinned, and the country became more savannah–like. It was our third day, when we first saw them – Mammoths.  A group of them.  The matriarch leading them, then several cows with calves.  Browsing leisurely through the trees.  They were enormous.  Brown hair, coming off in patches, chunks, streamers.  Grumbling, rumbling noises as they moved, with that slow, ponderous, implacable gait.  They seemed out-of-place.  They were out-of-place – better adapted to steppe country than to the savannah that surrounded us.  Their huge tusks were better suited to sweeping snow off covered ground, and their thick shaggy pelts were hardly necessary, at this time of year, in this climate.  Why they were this far south, I didn’t know.  They continued to browse, moving in a generally northeast direction.  I watched them for what seemed like hours, until they disappeared.  Even Devereaux seemed moved.  Until I heard him say, “Jesus, what a trophy that’d make.” 

 

The Clovis Mission: Ch. 4: Summers

 

Despite the very high regard I had for Leonard Carver, I thought he’d been remarkably foolhardy in the way he’d gone back.  It had been planned only as a brief scouting expedition, a chance for him to examine the countryside, in preparation for the summer’s fieldwork.  The summer project was to have involved his grad students and was going to last for six weeks.  But for this scouting expedition, he’d gone back alone, for a four-day look-see.  I thought that was stupid.  You don’t go into unfamiliar country, one swarming with big predators, alone, even if it’s only for a few days.  I still don’t know exactly how that came about.  Maybe because he was so well-known he could just do whatever he wanted.  But as a result, he was all alone back there – disastrous if anything went wrong, as it apparently had.  And, while we obviously knew exactly where he inserted, we didn’t know where or how far he’d wandered after jumping back in time.  And one man, alone, leaves a tiny footprint in a huge country.  So finding him might take us some time.

We prepared for the mission and trained for three weeks.  We trained in Englewood, Colorado.  White and Kramer didn’t stay there with me.  They  dropped me off, said that they’d take care of all of my personal and financial business while I was gone.  They were pretty nice, all things considered; shook my hand, petted Jack, wished me well.

The training center was fairly spartan, up at about 7,000 feet.  I was the first one into the training center.  On the second day, Dr. Steven Devereaux joined me as the second member of the team.  A specialist in the modeling and mechanics of the time travel apparatus, the technician who’d find out what had happened to the ASU site, and, hopefully, fix it.  He was a couple of years younger than me, thirty-two, I think.  Fairly slender, short dark hair.  Nerdy.  About what you’d expect from a techno-math-physicist.

Some of our training was academic – reviewing the maps we’d be bringing with us, learning how to send the time beacons.  Which, by the way, was easy, simple.  Food identification and preparation.

At night, we had to sleep with these mesh coverings over our head.  Neuro-linguistic programming, they told us.  Guaranteed, they said, to vastly accelerate the speed with which we’d pick up a new language.   It worked by electromagnetic stimulation of the speech centers in the brain.  I supposed it was in case we ran into any of the people living back there, back then, although I thought it was unlikely.  And, as far as I could tell, other than being slightly uncomfortable, the mesh headpiece and the neuro-linguistic training had absolutely no discernible effect.

For the most part, the training was – how shall I put this?  Stupid.  The firearms training was informative, and, somewhat to my surprise, fun.  Skinning and butchering animals, less so.  Otherwise, camping skills?  I already knew how to camp.  Saddling and unsaddling – I mean, c’mon, how long does that take to learn?  Not three weeks, that’s for damn sure.  Setting and sending the time beacons?  Easy.  Water purification?  Child’s play.  So why were we spending three weeks in “training?”

I thought, after they had pushed me so hard to decide instantly, that this delay was madness.  It made no sense to me.  If they were in such an all-fired hurry to get me committed, then why a three-week delay before sending us back?  Gene Kessler was the official in charge of the program, and I asked him about this after the third day.  He told me that this delay was only an “apparent” delay.  We would be sent back to three months before  Carver disappeared.  This, it was thought, would give us time to travel from St. Louis, to the Arizona State site, where Carver had last been, in time to find out what happened.

Time and distance.  We had a one-way journey of about 1400 miles, at a minimum.  But that was little more than a rough estimate, insofar as there were no roads, and we’d have to travel across entirely wild country.  We’d be at the mercy of the terrain, and would, I supposed, have to detour hither and yon to get there.  The team at DARPA figured that we’d average maybe twenty miles a day.  Sometimes more, of course, sometimes less, but they thought twenty miles/day was a reasonable estimate, for purposes of their time and distance calculations.  So, what? About two and half months to get there.  And a couple of weeks of “spare” time.

I knew a little about camping.  Devereaux had known nothing.  For Steven, the training was much more useful.  He’d never been camping, never ridden a horse, knew nothing about wilderness living. Not a clue about the guns.  An absolute wizard with the time beacons, though.  A very pleasant guy, I thought.  And a quick learner. He got the hang of everything pretty easily.

Lasher was a different story.  He didn’t show up until the middle of the second week.  Kessler had told us only that Lasher was Special Forces; long-range recon.  He apparently was going to be our security.   Tall, slim, dark hair, calm green eyes that missed nothing; an easy smooth walk; I had the sense that Lasher did everything gracefully, efficiently.  He looked very fit and very alert, and he was.  He didn’t say much.  He was a little older than me – probably late thirties, early forties.  No hint of a smile.  Two day old stubble.  Scruffy clothes.  A professional, I thought.  He gave off that calm, serious “Do not fuck with me” vibe.

Obviously, based on what Kessler had told us, Lasher didn’t need any training.  In fact, what he did was take over our training.  He coached us on our marksmanship, with all three weapons –rifle, shotgun, pistol.  He was surprisingly patient, and, it turned out, very good at teaching, at explaining to Devereaux and me what we were doing wrong.  And in a couple days, both of us were shooting much better.  Not marksmen, by any means, but we were at least respectable.

He also taught us about what was called the field protocol.  Basically, it was how to be alert in unfamiliar territory, how to move as a unit, how to use hand signals, all the stuff you’d want in a hostile environment, in enemy territory, or something.  I tried to explain to Lasher that we weren’t going into enemy territory.  Clovis fossils and artifacts were rare, ergo, the people known who made the Clovis points were thin on the ground.  Scarce.  Most of North America was uninhabited.  No people.  For all practical purposes, we’d be the only ones out there. We’d be unlikely to even see anybody.  And, even if we did, they’d have spears, and atlatls; we’d have rifles.  They’d have flint knives; we’d have pistols and Damascus steel knives.

Lasher just looked at me.  After a long minute, he said, “Yeah, well, we’re going to do it my way, anyway.”  That was it.  No discussion, no debate.  Just a given.

“Look, I don’t mind doing whatever,” I said. “I just don’t see why this is such a big deal to you.  There’s not going to be anyone out there, and even if there is, we outgun them by a mile.”

“I believe that is what Custer said,” Lasher replied.  And he sort of half-smiled.  I guess that was what he thought was a joke.  So Devereaux and I trained on, and learned the field protocol.

The biggest surprise was Jack.  He was a border collie mix, four years old, about.  I’d got him as a rescue puppy, and had sort of trained him, in a half-assed way.  What a great dog.  He was so smart, and full of energy.  I loved him.  And so, it turned out, did Lasher.  I saw him holding Jack’s head, and grabbing his fur, and talking to him.  So I was stunned when Lasher said “Too bad about Jack.  He’s a great dog.  But he’s not coming with us.”

“What?”

“Your dog, Jack.  He isn’t coming with us.  He’s a liability.  We can’t take him along.”

“Bullshit,” I said.  “Let’s go see Kessler.”  Lasher nodded, and he and I and Jack went into the field office to talk to Kessler.

I told him, “Look, Lasher just said that I can’t bring my dog with me.  You’ve got to talk to him.”

Lasher said, “The dog can’t come.  He isn’t trained.  He’ll spook the game.  He can’t be relied on.  We can’t bring him.”

“I see,” said Kessler.  “Well, Jeff,” he said, he said to me, “it seems to me that Mr. Lasher makes some very valid points.  I’m sure we can find someone to care for your dog while you’re gone.”

So, really, what did I think Kessler was going to do?  Referee?  Help us work it out?  What he did was, he sided with Lasher.  Of course he would.  Like he’d oppose what the security man said.

I drew on my extensive education, my doctorate, my scholarly research.  “Fuck you,” I said.  “If Jack isn’t going, then I’m not going, either.  I don’t’ care what you two have to do, but understand this – Jack goes where I go.  If he’s out, I’m out.”

I was beyond angry.  I was furious. The intensity of my rage surprised me, and even as I was swearing, part of me was watching, mortified.  He was it – other than my mom, he was the only family I had. We’d hiked for miles through the mountains and hills near my home.  He’d come with me on my fieldwork in the Green River country in Wyoming.  He’d hang out in my office on campus, while I taught class.  He was my companion.  So even though I was mortified, I was real damn serious.  I would not leave him.  Not in some kennel.  Not for four months.  Not at all.

“Look,” I said.  “He’s a border collie.  They’ve been bred to work with animals, to be partners with men.  Can’t we train him, so that he’ll work with us, not scare any animals away?”

Lasher just looked me.  Then, after a minute, he said, “Okay, we got a week.  If we can get him trained, I mean really trained, then the dog can come.  But if we don’t, if he isn’t perfect, then he isn’t coming.  And then you’ll have to do what you have to do.”  And then he left.

Kessler sighed.  “That’s Lasher.  Jesus.”

So, for the next 8 days, Lasher trained Jack and me.  He was like the freaking dog whisperer.  He had Jack trained unbelievably.  Come, go, stay, heel, go left, go right, come up; all the things that border collies are supposed to do.  And he had me trained, too. “He’s your dog, he told me, “He’s got to listen to you.   So here’s what you do.”  Over and over.  Until, at the end of that week, I got it.  I understood what he was talking about, and finally, Jack and I “clicked.”  We were a team.

And Sunday night, Lasher looked at me and Devereaux and Jack and said “That’s it. We’re ready.  We’ll go in tomorrow.”

What we brought:

Twelve  Horses.  A horse for each of us to ride, a spare horse for each of us (a “remount,” as the cavalry has it); two horses for Dr. Carver; three pack-horses; and a spare pack-horse.  The reliance on the horses was our greatest worry.  We were embarking on a round trip of approximately three thousand miles – as the crow flies.  And we were certainly not going to be able to travel that directly.  In all likelihood, we’d end up travelling well over three thousand miles.  The distance alone is an enormous burden for any animal. And this was travel in wilderness.  We’d be confronting all of the perils of the trip –deadfalls,  river crossings, animal attacks.  So we all thought that we were taking too few horses.  We had discussed this at length in the preparation sessions with the DARPA representatives, and Dr. Kessler.  Unfortunately, none of us saw any way around it. Kessler and the techs thought we might be able to take two, maybe three more horses than we did.  But then, paradoxically, we thought that to take more would make the size of the remuda unwieldy.  So we were stuck.  Twelve horses it was.

Oddly, Lasher seemed the least concerned about this.  “We can walk if we have to,” he said.  “And if Devereaux can get the ASU station up and running, we can just come back that way.”  Maybe we’d only go out by horse, but come back by. . . . magic.  (I still, even after all this time, can’t write “we’d come back by ‘time travel’” with a straight face.  It sounds like something out of Star Trek).  So, in the end, it was twelve horses.

What else?  Two of almost everything.  Two rifles each, two shotguns each, three pistols each.  (Lasher took four).  Clothes for all kinds of weather and temperature. Tents, sleeping bags, water filters.  This was somewhat controversial.  I argued that since we were going back before the modern era, i.e. before pollution, that there’d be no need to filter the water.  After all, the indigenous people  didn’t have micropore filters.

“Ever hear of Giardia?” Lasher asked.   So we took the filters.

We took a first aid kit – much bigger and more extensive than I had previously seen.  Lasher had  some training as a field medic, and Devereaux, it turned out, was an EMT.

We brought lots of gear: Pots, pans, salt, coffee, sugar.  Field guides to birds, to plants, to trees, to mushrooms.  I was the nature guide on this expedition; the one who was supposed to know what was safe to eat; how to traverse the varied ecosystems we’d encounter; how to deal with the natives, in the unlikely event that we met any; stuff like that.  And I thought the field guides would be useful.  From an evolutionary standpoint, twelve thousand years ago isn’t very long at all.  So the oaks and aspens, the fungi and mushrooms we’d see would be the same as the ones living today.  Stranger, though, to think about the animal population back then.  All the animals we know today – raccoons, robins, deer, ducks – all of them – were living there, back then.  But so were all kinds of other animals.  Animals no-one alive today has seen.  Mammoths, mastodons, giant sloths.  Passenger pigeons.  They’re all extinct now.  So it was quite a juxtaposition – bringing a field guide to birds, while worrying about running into a saber-toothed cat.

So what else? Packages and packages of freeze-dried foods.  They took up almost no space, to offset the fact that they had almost no taste.  Binoculars, axes, saws, knives. Dynamite.   Rope.  Needles and thread.  Lighters.  Matches. Traps.  Mirrors (for signaling).  Spare horseshoes, files, and nails.  More stuff than I had ever thought about.    Devereaux’s gear – the stuff he was going to use to repair the tesseract, if possible.

It seemed like a lot.  It was a lot.  But even as we practiced packing it on the pack-horses, I knew, I just knew, that it wouldn’t be enough.  Or rather, that we’d need something we didn’t have.  That was the first time, really, that the enormity of what we were doing hit me.  We’d be truly on our own.  I wondered how the mountain men had done it.  What if . . . What if . . .?  No doctor, no hospital, no cavalry to ride to the rescue.  It was a daunting task, and for the first time, I really knew it.

Personal stuff:  I brought pens, pencils, and paper;  several digital cameras and lots and lots of chips; a video camera; a magnifying glass. Here’s what I desperately wanted to bring, but couldn’t:  A complete dissection kit; a CT scanner; three hundred gallons of formaldehyde; five hundred pounds of plaster of paris; a cryogenics lab; a gene sequencer; 500 radio collars; six hundred tranquilizer darts, a gas chronometer; an ultra light aircraft for aerial surveys, and a tractor-trailer to haul it all in.

I brought Give your Heart to the Hawks, by Win Blevins, a book about the exploits of the mountain men.  I commend that book to anyone who is going off into the wilderness.   Devereaux, as it turned out, brought about two pounds of weed, and a bong, and rolling papers.  That was a surprise.  Lasher brought a big long, flat box, and  square (cubical) box, about 12 inches on a side.  And packs and packs of gum.

And so, off we went.

The insertion took place at the ground floor lab at Washington University.  The array was complex, to say the least, and I was surprised at the number of technicians running around, placing sensors here, and moving cables there.  The three of us, Jack, the horses, and all of our gear were placed in the center of the array, inside the tesseract.  We all had to go at the same time, because the vagaries of the insertion were such that successive “drops” might not land in exactly the same time.  That, I gather, was part of the reason why something as big as a plane or helicopter couldn’t have been used.

Kessler came up and shook hands with each of us, and wished us good luck.  And then, (and I loved him for it), he stooped and petted Jack.

And then he left, and we stood around for about three more minutes, while they calibrated whatever it was that needed calibrating, and then they counted backwards. Five.  Four.  Three . Two.  One.

Blink.

Transcendence.

Rest.

Stop.

The Clovis Mission: Ch. 3: Ross

Metairie, Louisiana.

Ross knew the General; well, the retired general now, Ambrose Maddox.  Forced, ever so delicately, into retirement after reports surfaced about some of his activities in Afghanistan.

And Ross knew about those activities, too.  After all, he had served with Maddox, before he’d been cashiered, along with several of his men.  Over fucking bullshit. Bastards.

No, wait.  Calm down a minute.  Be here now.  Ross regained his equilibrium.

“Thank you for coming, Colonel,” Maddox said. “It’s nice to know I can count on a few good men, when I need them.”

Ross nodded, and said, “Sir.”

“Colonel, we’ve got a situation, and we need your help.”

Ross thought, “We?”

Ross said, “Sir?”

“You know about this time travel thing, right?”

“Yes, Sir.”

“Three stations, right?  Fairbanks, St. Louis, and Arizona, right?”

“Yes, Sir.”

“Well those DARPA pukes been using it for some scientific research into cavemen or some such shit, and now they fucked up.”

“Sir?”

“First, the station at ASU – that’s Arizona State University, Colonel – the station there has gone down.  Deader than Uncle Harry’s Aunt.”

“Sir?”

“Second, they’ve sent a civilian –  a civilian, for Chrissakes! –  back to fix it.  Accompanied by another civilian, some professor of cavemanology or some such shit.  Well, Colonel, the people in the Defense Department, and my friends at NSA do not want some civilian running around out there, or back there, whatever.”

“No Sir,” Ross said.  He knew his lines.  And he knew this story was phony.  Maddox was out – O. U. T. – out.  No fucking way he was tied-in with Defense or NSA.  No.  The story was bullshit.  And obviously bullshit.  He was meant to see through it. So okay, why?

Because this is something else.  This is a black op.  This is the spooky stuff – covert.  Fair enough.

Didn’t matter much.  Ross knew what loyalty meant.  He knew that the General would take care of him – hell, he already had.  He’d run some serious interference protecting Ross and his boys after that last go-round over there.  So, yeah, Ross knew about loyalty.  Whatever the mission, he was in.

“No sir, we don’t want that at all,” Maddox continued. “It’s absolutely critical that we get that station repaired, and prepared – you know the President’s going to go out there to that Arizona station to give a speech, honor the fine men who perfected time travel, let the world know what we done.   And now that very station has gone down?  A little too coincidental, I think.”

“Colonel, we have reason to believe that this station has been brought down by an act of sabotage, and these purported civilians making their way out to Arizona present a clear and present danger to this great land of ours, to our science, to our technology.  These men are traitors.”

“That’s where you come in.  We want you to assemble a small team – no more than eight men.  Your men, Colonel.  We’ll task two scientists to accompany you.  We want you to jump back there, find those traitors, eliminate them, and then proceed to the ASU site, where the two scientists – our scientists –  will get the station up and running.”

Okay, Ross thought, so that’s the cover story – go back and wipe out these traitors.  Got it.  What’s the real story?

“Yes sir,” Ross said.

“We’re also going to send two more of our men with you, Colonel.  Good men.  Treat them with respect.  They are mission critical.”

Ah, this was a clue.  These guys, whoever they were, were part of this op, whatever it was.  Two of “our” men.  Whose men would that be?

“Understood, Sir.”

“We’ll keep working from our end, here.  Maybe we can jury rig a way to get that station fixed from this end.  But your job, Colonel, is to go back and get those two, then proceed to the station in Arizona.

“Yes, Sir,” Ross replied.

“Time is short, Colonel.  I want you to assemble the team within one week.  My aide, Swanson, has all the details.”

“Very good, General,” Ross said.

“That’s all, Colonel,” Maddox said.  “Dismissed.”

Ross had almost made it to the door when Maddox said “One last thing, colonel. Something that might interest you.”

“Sir?”

Those two civilians have some security on their trip.  Someone you know.”

“Sir?”

“Daniel Lasher, Colonel. Master gunnery sergeant Daniel Lasher.”

The Clovis Mission: Ch. 2: Summers

Things started happening real fast.

First, to my amazement, Dean Mendelsohn got out of the helicopter, with luggage.

“I’ll stay and wind things up here, for you,” he said.

The Dean?  Here?  That sly old devil – still wanted to show he could do fieldwork, I guess.  Or maybe this was so urgent that they didn’t have anyone else to come in for me.

But either way, this was happening fast, fast.

Because as he was stepping out of the chopper, they told me to pack up my gear, because I was flying out with them.

So within an hour of their arrival I found myself flying across country with two men from DARPA, heading for training for this mission.

Here’s the thing:  I didn’t know anything about time travel.  I still don’t, really, not the complexities of the math, or the real science behind it.   I’d heard or read that we couldn’t change the past, but that we could learn from it.  In other words, no matter what you or I did 12,000 years ago, wouldn’t matter – we’d end up exactly as we were.   That always seemed a little weird to me, but I didn’t really think about it very much.

And when I did think about it, it was usually to envy someone like Carver, who had had the opportunity to actually go back in time and study the Pleistocene.

So as we flew, White tried to explain time travel to me.

“Let’s start with time travel itself, first, before we talk about the beacons, okay?”

I thought that sounded like a good plan.

“As you know (I hadn’t), the secret to time travel is quantum entanglement – spooky action at a distance.  Turns out it works over time as well as space.”

“But it requires amazingly accurate pinpoint computation, to synchronize this ‘now’ with that ‘then.’  We’re talking about the kind of calculations that make supercomputers seem slow.   It’s so slow and expensive that we’ve only got these three stations up and running, ASU, St. Louis, and Fairbanks.”

“Yes, but how does it actually work?  What happens?”

“Why, from your standpoint, that of the time traveler, it’s easy and painless.  The transmitter, say the one at Washington University, is a big box.  They call it a tesseract – it’s a multi-dimensional cube.  They build a smaller one inside it, and that is sent back to the time you’re aiming at.  Then, you and your companions and your gear stand within the main tesseract, it does quantum scanning, and transmits you to the slightly smaller tesseract which has been prepositioned at the time you wish to visit.”

“Wait – it transmits me?  How?  Am I de-materialized?  What?”

This started sounding a little scary.

“No, not at all.  ‘Transmits’ is just the term we use for the process.  What happens is that the quantum field set up within the tesseract substitutes the previously chosen time for the present.  That is the variable that changes.  You are within the field, and the three physical dimensions –- length, height, width, you know  —  remain the same, but the fourth dimension –  time – is switched.  That’s the math part that we’ve been talking about.”

“Yeah, right, spooky action at a distance.  Got it.  But it’s safe, you say?”

“Oh yes.  You stand there, or sit, for that matter, while you’re scanned, and then the tesseract changes the one variable – the time in which you exist – substitutes the past for the present.

“And that’s it?”

“Yes, that’s it.  You feel a flash or some people have described at as a twitch, or a tingle, and look around, and you’ll see that instead of being in the lab at Wash. U., you’re back sometime in the past – whatever time you’ve picked.”

And, he explained, you come back the same way – step into the tesseract that is back when and where you are, and it does its magic and the one variable that changes – time – flips, and instead of being back there ten thousand years ago, here you are, back in the present.

But as it turned out, time travel had some odd, or at least not-obvious limitations.  Kramer said that this was party due to the fact that time travel was so new, and partly, I think, because they didn’t fully understand the math or physics that underlay it.  They could make it work – they had made it work –but apparently no one completely understood how it worked.  But he explained to me what they had learned.

Kramer:  “First, we have established that one cannot use the past to change the present – one cannot go back in time and kill Hitler, for example, tempting though that might be.”

Yeah?  Have they tried?  I’d sure as hell try.

So I asked.  “Did you guys try?”

Kramer glared at me.   “Damn right we tried.  Nailed him, too.  Only it doesn’t matter.”

“What?  Why not?” I asked. “Why doesn’t our present change, if you go back in time and change something in our past?  I don’t get it.”

“Excellent question,” White said smoothly.  “Why this is – that is not well understood.   The prevailing theory, though, is that the present, our present, is immutable, because of a theory of multiverses.  That is, we don’t travel back into our past per se, but rather back into a past that the time travel process itself calls into being, a past identical in all ways to our own, with the simple problem that whatever is done back there, has no change on the present we return to.”

“In other words,” he said, “you can go back in time, kill all the Hitlers you want, but when you come back to our time, our history includes Hitler; is unchanged.”

But wait a minute.

“Wait,” I said.  “Is the past we go to the real past, or a fake past, called up out of the ether?”

“Excellent question,” he said again.  Guy must have given this lecture, answered all these question hundreds of times before.  He was unflappable.

“It’s both,” he said. “It’s the real past – we see the actual events that happened, observe historical events that we know happened – all the data matches.  But at the same time, it’s parallel, dual, identical to our past, but not our past.  It’s a past on a different track:  equally real, equally viable, solid, real.  It exists.  But there’s a disconnect somewhere.  Like I say, you can kill Hitler back there, but whatever you do, the present you return to – our present – includes the bloody history of Europe in the thirties, and World War II.”

“That’s why the program has evolved as it has.  All time travel can do is let us learn from the past.  We cannot change the past we know in our present.  That we cannot do.  But we can change our future, change our behavior in the future.  If we learn, for example, why mammoths became extinct in North America about twelve thousand years ago, maybe we can prevent some other extinction events in our time.”

Kramer jumped back in.  “And time travel has – so far, at least – strict, but poorly understood limits on retrieval.”

“On retrieval?”

“Yes, bringing material forward, from the past.”

“It’s a phenomenon called “quantum identification.”  Each time traveler, and all of his or her equipment must first be scanned at the quantum level, before transmission into the past. This scan provides the template, as it were for retrieval back to our present. “

“But only what is scanned can be retrieved.  In practical terms, what this means, at least at present, is that only what is sent back in time can be retrieved, brought forward to the present.  So, no mammoths, no cave men, not even tissue samples, as yet, can be brought back.”

Now that’s weird.  Why not?  Why can’t they bring anything back?   Look I know I’m not a physicist, and I’m sure I could never understand the math, but it seemed so unfair.  I mean, wouldn’t it be cool if you could go back in time, and bring back a baby mammoth or something?  Can’t they figure that part of it out?

Matter is energy, I guess, and I know we’re not talking about travel to a place, but travel to a different time.  Maybe a different kind of energy?  I don’t know.  And White and Kramer didn’t – or couldn’t – explain it in a way I could understand.

But I got the rule, though.  That I understood.  Nothing from back then comes back to here and now.  But not clear, and not fair.

He was still talking.

“Now this rule can be bent, even if we can’t yet break it.  So, for example, data stored electronically can be brought back – photos on digitized chips, digitally stored voice or video recordings.  Drawings, notes, those are fine too.”

Well, that’s interesting.  I’ll bring a sketch pad, to go with my cameras.

“But intriguingly, that is it, at least for now.  Nothing more can be brought back.  Even the dirt that one would expect to find on the shoes or clothing of returning time travelers does not return to the present.  We haven’t found even a microbe, or bacteria.”

“So the problem of quantum identification is an intriguing, and perplexing one.”

Well, those, it seemed, were the rules of time travel.  The math supporting all this was, I was given to understand, remarkably complex, incredibly sophisticated.  I am not a mathematician, thankfully, so they didn’t even try to explain that all to me.

On to the time beacons.

The way it worked was that from any of the three centers, travelers would be shifted back in time, but not transported through space.  They’d end up right where they had been – in Arizona, or Missouri, or Alaska, simply back in an earlier time.  All well and good, but then your time traveler wants to actually, you know, travel.  Walk around, see the country, do some research.  So for the duration of that trip, the time traveler is wandering around, travelling, doing whatever.

So each traveler is given little beacons, about the size of a tea light, to send at the same time every day, sort of like checking in, saying all is well.  It just triggers a flash on the tesseract sensors, letting the monitors know where you are (since the terrain then is the same geographically as the terrain now), and that you’re still alive, well enough to send the beacon.  And every traveler was given an emergency beacon, saying, basically, “send help now!”

And, up until now, it had been safe.  So long as a given station kept running, the time traveler could always just come home.  Or if he or she needed help, a second team could be sent back to help out.  Which they told me had never been necessary.

And Carver had gone back, successfully, since he’d sent two of the time beacons.  But three days ago, Carver hadn’t sent the beacon.  And none had come in since.  And then, yesterday, the telemetry and chronometers and everything at ASU had gone offline.  Everything had been debugged, power cables checked, tech guys called in – everything.  But for some reason, stubbornly, obstinately, the station remained down.  Never happened before.  Shouldn’t have happened now.  In fact, it was theoretically impossible.

The only problem was that it had happened.  An “oh shit!” moment for the people at DARPA.  Because they couldn’t tell what had happened to Carver, and because the station was down, they couldn’t just zap someone back to find out.

But DARPA had a protocol for situations like this.  Even though, as I say, it was theoretically impossible, they had planned for it.

And now, I was part of that plan.