* * * * *

The many tubes fluoresced, flared up in pulsing waves of violet and
pink: there were gray bars of invisibility or areas of air in which
nothing visible showed. There came the faint, crackling hum of machinery
rather like a swarm of wasps in anger. Blue and gray thread of fire spat
across the antenna. The odor of ozone came to Mrs. Baker's nostrils,
and the acid odors burned her lungs.

She was staring at him, staring at the professor's face. She half rose
from her chair, and uttered a little cry.

The eyes had changed, no longer were they cold, impersonal, the eyes of
a man who prided himself on the fact that he kept his arteries soft and
his heart hard; they were loving, soft eyes.

"Allen," she cried.

Yes, without doubt, the eyes of her son were looking at her out of the
body of Professor Ramsey Burr.

"Mother," he said gently. "Don't be alarmed. It is successful. I am
here, in Professor Burr's body."

"Yes," she cried, hysterically. It was too weird to believe. It seemed
dim to her, unearthly.

"Are you all right, darling?" she asked timidly.

"Yes. I felt nothing beyond a momentary giddy spell, a bit of nausea and
mental stiffness. It was strange, and I have a slight headache. However,
all is well."

He grinned at her, laughed with the voice which was not his, yet which
she recognized as directed by her son's spirit. The laugh was cracked
and unlike Allen's whole-hearted mirth, yet she smiled in sympathy.

"Yes, the first part is a success," said the man. "Our egos have
interchanged. Soon, our bodies will undergo the transformation, and then
I must keep under cover. I dislike Burr--yet he is a great man. He has
saved me. I suppose the slight headache which I feel is one bequeathed
me by Burr. I hope he inherits my shivers and terrors and the neuralgia
for the time being, so he will get some idea of what I have undergone."

He had got down from the oscillating platform, the spirit of her son in
Ramsey's body.

"What--what are you doing now?" she asked.

"I must carry out the rest of it myself," he said. "Burr directed me
when we talked yesterday. It is more difficult when one subject is out
of the laboratory, and the tubes must be checked."

* * * * *

He went carefully about his work, and she saw him replacing four of the
tubes with others, new ones, which were ready at hand. Though it was the
body of Ramsey Burr, the m