“You can't do experiments on my boyfriend,” said Ellie. “I absolutely forbid it. It must be illegal, or unethical, or something.”

Credit: Jacey

“He volunteered,” said Jamie. “He gets paid and all legal requirements are being met.”

“Does Mum know how much you're spending?”

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Although her little brother was a millionaire thanks to his inventions and patents, their mother controlled the money until he was 18.

“She won't mind.”

“I love Claude. You better not hurt him.”

“You can always get another one. You change them all the time.”

“So what is this about?” she said, as an alternative to slapping him.

'Invisible earphones.”

“Well that's good.”

She liked the idea. No set of earphones ever made looked remotely cool. She loved listening to music but didn't want to go around with earphones on all day looking like a loser.

“How will you do it?”

Jamie's gifts did not include the ability to explain his ideas to normal people. There was something about magnetosomes, tiny things with iron crystals in them.

“They are the compass of homing pigeons,” said Jamie, and then immediately contradicted himself by saying that what birds used was smaller and more subtle. “It may not work, but the point is that if these things can align themselves with a magnetic field then we can use a magnetic field to move them and induce signals directly into nerves.”

“The point is that you want to inject tiny particles into Claude's brain. Well you can't.”

But he could. Ellie's appeal to their mother was in vain.

“There's nothing to worry about, dear,” she said. “Claude is just one of nine students from your university who signed up for the experiment. It's being run by a licensed human testing organization and there's a full review and risk assessment. Jamie showed me.”

Ellie nodded and smiled. She always smiled at her mother when she was trying to change her mind. Ellie had googled the firm and the individual doctors but found nothing she could use to stop the trials from going ahead.

“But it's a lot of money. Even Jamie says he doesn't know if it will work.”

“Oh don't you worry about that. The accountants will offset it against tax. It won't cost anything to try and it might be a big success.”

There was no change in Claude. He had always been given to acts of spontaneous generosity, and now that he had more money Ellie got more lovely surprises. But her brother was glum. The hidden collar magnets produced no sounds. Bigger magnets did nothing. The volunteers had even put their heads into some sort of super magnet. None of them heard induced sounds. The trials had failed. She texted Jamie an invitation for coffee so she could cheer him up.

She had Claude on her arm when they met. Jamie gave him the polite, unengaged smile that he gave to most people.

“Shall we go to Coffee Delight?” she said.

“Let's go to Midnight Mocha.”

It was typical Jamie. CD was just down the block and it was bright, bustling and super popular — everyone was there. Midnight Mocha was gloomy and usually empty. But it was what Jamie liked and she was doing this for him. She started down the well-worn route but Claude's strong warm arm steered her away from it.

“Let's go this way,” he said.

They took a funny route through the crisp autumn air, cutting through a park, walking on the grass instead of following the paths and then took a sharp turn at the end, not the shortest way but nice. Jamie paced beside them, messing with his mobile phone.

Ellie tried to cheer Jamie up over cappuccino, but he was even more introverted than usual. After one of Claude's jokes Jamie looked up.

“When we walked here you were always heading 17° west of south,” said Jamie. “Why did you do that?”

“Just walking,” said Claude. “At least we got here.”

He took the opportunity to launch into a hilarious story that left Ellie doubled up with laughter and even brought a smile to Jamie's face. When they left Jamie paid for everything: coffees, cakes and refills.

“I can charge it to the project,” he said.

It was a first. She must have succeeded in cheering him up; her tight-fisted brother never paid for anyone else.

Two mornings later, tears were streaming down Ellie's face as she tried to eat her low-fat yogurt breakfast. She wiped them away as Jamie came into the kitchen.

“Is Claude leaving you?”

She sat up, astonished. Jamie could hardly tell if other people liked or disliked him. He had never had any sort of relationship in his life and was hopeless at picking up the most basic social cues.

“How did you know?'

“The way he walked to Midnight Mocha. If you apply the magnetic declination to that heading, he was walking straight away from magnetic north.

“But Jamie! He's quitting university. He's going to Florida. I'll never see him again!”

“Do you love him enough to wait for him?”

“Oh, Jamie. You know I do.”

“Then it will be OK. He's just migrating. Don't worry, he'll be back in the spring. Footnote 1