*****
You've hiked through Snake Canyon once before while visiting your Uncle Howard at Red Creek Ranch, but you never noticed any cave entrance.  It looks as though a recent rock slide has uncovered it.

Though the late afternoon sun is striking the opening of the cave, the interior remains in total darkness.  You step inside a few feet, trying to get an idea of how big it is.  As your eyes become used to the dark, you see what looks like a tunnel ahead, dimly lit by some kind of phosphorescent material on its walls.  The tunnel walls are smooth, as if they were shaped by running water.  After twenty feet or so, the tunnel curves.  You wonder where it leads.  You venture in a bit further, but you feel nervous being alone in such a strange place.  You turn and hurry out.

A thunderstorm may be coming, judging by how dark it looks outside.  Suddenly you realize the sun has long since set, and the landscape is lit only by the pale light of the full moon.  You must have fallen asleep and woken up hours later.  But then you remember something even more strange.  Just last evening, the moon was only a slim crescent in the sky.

You wonder how long you've been in the cave.  You are not hungry.  You don't feel you have been sleeping.  you wonder whether to try to walk back home by moonlight or whether to wait for dawn, rather than risk losing your footing on the steep and rocky trail.

[If you decide to wait, turn to page 5.]

You wait until morning, but, as the rosy wisps of dawn begin to light the eastern sky, a chill and forbidding wind begins to blow.

[If you brave the freezing wind to see more of the world about you, turn to page 16.]

You resolutely trudge along a rocky ridge.  It has been cleared of whirling snow by the fierce wind, which bites and blows against your body.

The world seems transformed, and much for the worse.  You must find a house or a cabin -- people who can help you -- or you will die.

As you ponder your fate, you stumble and fall, plunging into a deep crevasse.  You black out and later awaken, still shivering, but in a warmer place at least.  By the dim amber light, you can see that somehow you have fallen back into one of the chambers in the Cave of Time.  A passageway leads to the right, another to the left.  Does one lead to the future and one to the past?

[If you enter the left-hand passageway, turn to page 24.]

You follow the left passageway.  It leads upward to the surface.  before you, a grassy meadow slopes down to a clear, fast-flowing stream; beyond it are pine-covered foothills stretching in the distance toward snow-covered peaks.  You might be in Wyoming in your own time, but, whatever time it is, the world you see appears to be a hospitable one.

You notice a herd of buffalo grazing.  But nowhere can you see a house, or fence, or road, or any sign of human presence.  It is possible you are living hundreds, perhaps thousands, of years ago.

You gaze upward.  One of the puffy, white cumulus clouds is moving in a strange fashion.  It is descending!  A spaceship is landing right before your eyes, only a few hundred yards away!

[If you hide from view, turn to page 38.]

You feel you must be far in the future.  Are you really looking at an alien spaceship?  If so, you would rather watch from a safe distance.  You climb rapidly up the hill -- wondering how you got to this strange time.

Ahead of you is a niche in the rocks.  You step inside.  You realize you are in the bottom of the crevasse you fell into from the Ice Age.  Even if you wanted to get back to that time, there is no way you could do so.  You keep walking.  Eventually your approach open ground on the opposite side of the hill.

Now you can see a vast stretch of open country -- hilly, rocky, and mostly barren.  Yet thousands of people are constructing a huge wall!  All over the landscape you see oxen pulling carts filled with rocks.  The wall is at least twenty feet high and extends as far as the eye can see.

Ladders are strung up against the wall, and on every rung a man or woman is stationed.  They hand rocks up one to another to the top of the wall. You find this sight hardly less amazing than the sight of the alien spaceship, for it appears that you are witnessing the building of the Great Wall of China.

[If you go up to the wall builders, turn to page 82.]

You go up to the base of the wall where the people are working. When they see you, they imagine you are a spy from some unknown tribe. Some of the guards capture you and force you sit on a pile of rocks while they talk about you.

After a while they point to one of the ladders. Two other people force you to start handing up bricks. You realize that you have been conscripted to work building a wall twenty feet high, twelve feet wide, and 1,400 miles long. You calculate it will take about ten billion rocks to build the wall. You wonder how many of them you will lift before you can escape -- if you ever do.

The End