“Perhaps you could explain to Mrs. Tilbury how this test works. I’m concerned that she’s being treated rather like a laboratory rat.”

“Oh, surely not,” Dr. Bamber protested.

“I didn’t put it quite like that,” Gretchen said, smoothing his ruffled feathers. “I only felt I was being kept somewhat in the dark.”

“Then we must provide illumination.” He picked up his fountain pen and began to fiddle with the cap. “There’s nothing I like more than talking about my field, but most patients find the detail rather dull.”

“Maybe Mrs. Tilbury should be considered more of a volunteer than a patient. Since she’s not unwell.” Jean’s distrust of doctors, even the helpful ones, was never far from the surface.

“Of course. What we are doing is a serum protein electrophoresis test. Serum is the liquid left behind when the red and white blood cells have been removed from the blood. It contains proteins—albumin and various globulins, alpha, beta, gamma. These carry different electrical charges and they will move in fluid to display a distinctive pattern. We usually use this test to diagnose disease, but in this case we are only interested in comparing the two patterns—yours and Margaret’s—for any variation.” He beamed. “So all we need is a small sample of blood from you both and we can get to work.”

“I see,” said Gretchen serenely. “Thank you.”

Margaret’s brow had been furrowed with concentration while this explanation lasted. Jean couldn’t help wondering if the angel voices, keen curators of esoteric vocabulary, were filing globulin and electrophoresis away for another day.

There was a tap on the door and, as if she had been awaiting some secret signal, a nurse appeared to take mother and daughter to the phlebotomy department.

As soon as Gretchen and Margaret returned from the lab, Dr. Bamber’s secretary appeared with the promised refreshments. With only three chairs and two slices of toast between four people, there was no chance of a convivial tea party developing. As non-fasters, Jean and Doctor Bamber abstained from toast, and he drank his tea standing up, looming over the three visitors, rocking back and forth on his heels in his awkwardness.

Gretchen, in any case, was not disposed to linger. She drank her tea quickly, gave half her uneaten slice of toast to Margaret and started to button her jacket as a sign of readiness to depart. Outside on the pavement, she turned to Jean with the unmistakable hesitancy of someone about to ask a favor.

“I wonder. Tell me if you think it is a bit of an imposition.”

“What?” said Jean.

Gretchen looked at her watch. “I’ve got a few errands to run while I’m up in town. It seems a bit of a waste not to do them while I’m here, but Margaret really needs to get back to school.”

“No, I don’t,” said Margaret. “It’s English comprehension and I’m already the best at that anyway.”

“You can’t keep having days off.”

“You’d like me to take Margaret back to school?” said Jean, recognizing from her own dealings with Mrs. Melsom that there was a tendency for the petitioner in these situations to rely on inference. “It would be a pleasure.”