“Sure,” we say in unison, and duck between the wagons and follow him up the gentle slope.

The prairie stretches endlessly before us, an expanse of black that is gradually brightening to green before the rising sun. About half a mile away is the strangest storm cloud I’ve ever seen. It hugs the earth, a rolling mass sweeping across the horizon.

“That’s no storm,” Jefferson says.

“Buffalo!” Craven shouts. “Run back and warn everyone. They must stay in the wagons!”

Jefferson reacts instantly, sprinting away with his long legs, hollering as he goes.

But I’m frozen by the sight. It’s not possible. How can there be so many of one animal in the world? They are a frothing sea of heads bowed low and whipping tails and flying mud.

Craven grabs my arm. “C’mon, you fool—unless you want to get trampled.”

His words unstick my legs. We turn and run.

Jefferson’s warning cries have drawn everyone out. They linger about the wagons, sleepily curious. Jeff grabs Henry and forces him toward his wagon, then does the same to Jasper. No one is moving fast enough.

“Hide!” I scream as we run down the slope. “Hide!”

I know the exact moment the buffalo crest the rise behind me, because curiosity turns to terror. Men blunder over their rifles and ramrods while mothers grab their children and run for cover. Jefferson hefts Andy under one arm and drags Olive by the hand, toward Mrs. Joyner. Thunder vibrates all around me. I expect hooves to impale me at any moment.

Yards short of safety, my toe catches on a hole in the cattle-churned sod. I fly out, hit the ground hard. My lungs won’t draw air. My head spins. I’m scrambling to my feet when I feel the first hard impact on my back.

I scream, but it’s only Jefferson’s hands. He grabs me by my suspenders and the waist of my pants and heaves me up onto the wagon bench. I turn to pull him to safety beside me, but he has already rolled between the wheels to the other side. He glances back, just quick enough to make sure I’m secure, then he starts herding families toward the shelter of their wagons.

A rifle booms a few feet away, and I duck. Buffalo pour down the slope like a muddy brown flood. More gunshots crack the air, though I barely hear them through the roar of hooves. A few buffalo drop and tumble, but there are so many it makes no difference. Major Craven rips off his shirt and stands before the lead wagon. He whips it through the air and hollers, as if the buffalo are nothing but giant cows, easily herded by a little yelling and waving.

They are not cows. A great horned creature with a giant black head is nearly upon him. Finally, he turns to run.

“Major!” I scream.