to coming down, as well as going up."

"Gravity is action and you're the reaction in that case," the lieutenant observed.

"Not exactly. The escape velocity of the earth is gravity in reverse—if we can twist our minds around to think of it that way. We manufacture the escape velocity with our rocket fuel and use it to neutralize gravity. An object going 6.9 miles a second goes far enough around the earth in a second that the earth's curvature doesn't catch up with it, so to speak."

"I hope you're sure of your reactions, although it doesn't make a lot of difference if we get this message down."

"We're hitting the atmosphere at a speed close to the escape velocity of the earth. If we were going that speed we'd never get any closer to the surface. But we're being slowed so that we're falling—not very fast, but fast enough. Our speed around the earth is about 6.9 miles a second, minus a few decimals. Our speed toward the earth isn't very fast—I'd say a few feet a second. Our only problem now is to stop our forward speed without speeding our downward speed."

"I don't suppose you're very optimistic about it?" the lieutenant asked, hopefully.

"No," the captain admitted, "but we can try. You've seen airplanes land at speeds of one hundred miles an hour or more. That was their speed forward. Their speed downward was measured in feet per minute. That's our problem now. We've got to land like an airplane—make a deadstick landing without crashing."

"Oh we might be able to land, but the minute we touch, some of our forward speed is going to get us into trouble. Remember, an airplane has wheels."

Captain Bonnet pointed to a small globe painted with a map of the world. His finger touched a dot in the South Pacific near the Antarctic continent at 60 degrees south latitude and 120 degrees west longitude.

"That's Dougherty Island," he said. "Between that island and San Francisco are 6,300 miles of empty Pacific ocean. We're going to try to land near Dougherty Island at a speed so fast we'll barely touch the surface of the water. But as we touch the water, the frictional heat of the sides of our space ship will transform the water instantly into steam. The steam will cushion our ship against shock and decelerate us rapidly—but not too rapidly for endurance. The stop will be rough, but we can take it. We ought to be able to stop in 6,300 miles."

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