Until I got to the part about the head in the Thermos bottle, I figured it was just another technical story about the unlikely science of cryonics.

The head part stopped me, though. That was a wrinkle I hadn’t considered before.

Inside the head of Thomas Donaldson, a 46-year-old mathematician in California, is a brain tumor. Doctors can’t operate, and chemotherapy so far has been able only to reduce the size of the tumor, not eliminate it.

There is a good chance that Donaldson, who is married and childless, will be dead within five years.

Taking his “never say die” philosophy to extremes, Donaldson has gone to court for permission to have his head frozen by the people at Alcor Life Extension, a leading cryonics company in California.

Donaldson wants it done before he dies — before the tumor is able to destroy his mental faculties and change his personality. That way, his head (wherein lies Donaldson’s brain, wherein lies Donaldson) can be revived from its state of suspension “sometime in the future,” when doctors will have discovered the means of curing his disease.

His restored brain will then be reattached to a healthy body, after which Donaldson will presumably go back into the world as a new man — or half a new man.

About 300 people have signed up with Alcor to have themselves frozen at death. A patient is first given barbiturates or anesthetics, and blood is replaced with chemicals. Technicians freeze the body over two weeks. A patient can choose to have the head removed and placed in a Thermoslike device that keeps it chilled to 320 degrees below zero.

About 13 heads already are frozen at Alcor, and nine people have had their bodies frozen whole. The company charges $100,000 for a full-body freeze, and $35,000 for just a head. Like everything else, even cheating death is a matter of money. Since Donaldson wants to go the cheaper route, I am curious to know whether he doesn’t like his body or he just doesn’t have the extra cash.

The idea is luridly fascinating, something Ray Bradbury or Isaac Asimov might have conjured up for a book. Scientists are skeptical, though. One of them scoffed that a frozen person would look like “a wilted flower” when he thawed. But who’s to say it can’t work? Test tube babies were once inconceivable, pardon the pun.

Assuming the people at Alcor can pull it off, there are a few questions that need to be answered before we all decide to become medical Rip van Winkles and freeze our heads:

If someone like Donaldson is frozen at 46 years of age, and is revived in 30 years, how old will he be? If he is 76, will he be instantly eligible for Social Security benefits and senior-citizen discounts at restaurants, even though he hasn’t worked a day since 1990?

If he is still 46 in 30 years, will he leave his elderly wife and go looking for someone his own age?

What about his new body? Will there be companies selling bodies to go with heads like Donaldson’s? Will Alcor get into that business, too, selling the bodies of people who went for just the frozen-head deal?

What if they attach Donaldson’s head to a new body before thawing it and removing the brain tumor? Would Donaldson then have to accept whatever body he wakes up with, even if it looks like Willard Scott’s? What if he gets his old mathematician’s body back, instead of the athletic one he hoped for?

If they thaw Donaldson first so he can choose his own body, will they prop his head on top of each one and let him look in the mirror? Will perfect bodies cost more than imperfect ones? Can he be biracial? Bisexual? Will they charge him by the pound?

Will they accept a personal check from a guy who has no I.D.s on his person? A guy who doesn’t even have a person?

If he chooses an 18-year-old body, will his 46-year-old mind be able to keep up with it?

Will they use bolts?

Does he have to pay back the life insurance money his wife got when he was declared dead in 1990? With interest?

Will we have people wandering around in turtlenecks who are younger than their children?

Will there be a world to come back to? If not, does Donaldson get his money back? From whom?

Will a simple head cold be life-threatening?

“I might be brought back to settle some planet far away,” Donaldson told reporters. “That wouldn’t be too bad, would it?”

Perhaps not, Mr. Donaldson. But have you considered freezer burn?