"That's good enough for us," said Dr. Whitehead, director of the Pasadena work. "Everything we've done here has failed so far. A direct chemical approach seems out of the question. We'll start with one, but I think a dozen projectors, at least, are possible for this area."

Pasadena also reported a new radio contact with Calcutta, and promised to pass the word on to them and to Tokyo. When they closed down the transmitter after midnight, Ken totaled the number of projectors promised with reasonable certainty of having the promises fulfilled. There were eighty.

"It may take a year," his father said, "or it may take 10 years, but now we know, without a doubt, that we can someday get our atmosphere back as it was before the comet."


Chapter 20.
Reconstruction

On the twentieth of January the comet reached its closest approach to Earth. It was then less than three million miles away. In the realm of the stars, this was virtually a collision, and if the head of the comet had been composed of anything more than highly rarefied gases it would have caused tremendous upheavals and tidal waves.

There were none of these. Only the dust.

Ken arose at dawn that day and went into the yard to watch the rising of the golden enemy a little before the sun came over the eastern hills. He doubted whether anyone else was aware it was closer today than it had been before, or ever would be again. He doubted there would be much scientific interest in the event, anywhere in the world.

In the observatory, he opened the dome and adjusted the telescope to take a few pictures and spectrograms. He remembered when he had done this, a long time ago, with high excitement and curiosity, and he remembered later times when he had looked up with a bitter hate in his heart for the impersonal object in the sky.

Now, he felt nothing. He was aware only of a kind of deadness in his emotions with respect to the comet.