maged astronavigation instrument has been replaced."

"You never went to the office, father? You never went at all?"

"No, my son. My stand-in worked at the office in my place. I instilled
in your mother's mind an intense dislike and fear of the office to keep
her from ever coming face to face with the stand-in. She might have
noticed the difference. But I had to have a stand-in, as a safeguard.
Your mother _might_ have gone to the office despite the mental block."

"She's gone now, father. Why did you send for her?"

"To avoid what she would call a scene, my son. That I could not endure.
I had the stand-in summon her on the office telephone, then I withdrew
all vitality from it. She will find it quite lifeless. But it does not
matter now. When she returns we will be gone."

"Was constructing the stand-in difficult, father?"

"Not for me, my son. On Mars we have many androids, each constructed to
perform a specific task. Some are ingenious beyond belief--or would seem
so to Earthmen."

There was a pause, then the weaker of the two voices said, "I will miss
my mother. She tried to make me happy. She tried very hard."

"You must be brave and strong, my son. We are eagles, you and I. Your
mother is a sparrow, gentle and dun-colored. I shall always remember her
with tenderness. You want to go with me, don't you?"

"Yes, father. Oh, yes!"

"Then come, my son. We must hurry. Your mother will be returning any
minute now."

Sally stood motionless, listening to the voices like a spectator sitting
before a television screen. A spectator can see as well as hear, and
Sally could visualize her son's pale, eager face so clearly there was no
need for her to move forward into the room.

She could not move. And nothing on Earth could have wrenched a tortured
cry from her. Grief and shock may paralyze the mind and will, but
Sally's will was not paralyzed.

It was as if the thread of her life had been cut, with only one light
left burning. Tommy was that light. He would never change. He would go
from her forever. But he would always be her son.

The door of Tommy's room opened and Tommy and his father came out into
the hall. Sally stepped back into shadows and watched them walk quickly
down the hall to the stairs, their voices low, hushed. She heard them
descend the stairs, their footsteps dwindle, die away into silence ...

_You'll see a light, Sally, a great glow lighting up the sky. The ship
must be very beautiful. For