as I could, reconstituting my exceedingly devious
homeward route.

"Your retreat was masterly," he remarked with a broad smile. "I should
think that it would have utterly defeated any pursuer; and the only pity
is that it was probably wasted on the desert air. Your pursuer had by
that time become a fugitive. But you were wise to take these
precautions, for, of course, Weiss might have followed you."

"But I thought he was in Hamburg?"

"Did you? You are a very confiding young gentleman, for a budding
medical jurist. Of course we don't know that he is not; but the fact
that he has given Hamburg as his present whereabouts establishes a
strong presumption that he is somewhere else. I only hope that he has
not located you, and, from what you tell me of your later methods, I
fancy that you would have shaken him off even if he had started to
follow you from the tea-shop."

"I hope so too. But how did that woman manage to stick to me in that
way? What was the mistake we made?"

Thorndyke laughed grimly. "It was a perfectly asinine mistake, Jervis.
You started up Kennington Park Road on a leisurely, jog-trotting
omnibus, and neither you nor I remembered what there is underneath
Kennington Park Road."

"Underneath!" I exclaimed, completely puzzled for the moment. Then,
suddenly realizing what he meant, "Of course!" I exclaimed. "Idiot that
I am! You mean the electric railway?"

"Yes. That explains everything. Mrs. Schallibaum must have watched us
from some shop and quietly followed us up the lane. There were a good
many women about and several were walking in our direction. There was
nothing to distinguish her from the others unless you had recognized
her, which you would hardly have been able to do if she had worn a veil
and kept at a fair distance. At least I think not."

"No," I agreed, "I certainly should not. I had only seen her in a
half-dark room. In outdoor clothes and with a veil, I should never have
been able to identify her without very close inspection. Besides there
was the disguise or make-up."

"Not at that time. She would hardly come disguised to her own house,
for it might have led to her being challenged and asked who she was. I
think we may take it that there was no actual disguise, although she
would probably wear a shady hat and a veil; which would have prevented
either of us from picking her out from the other women in the street."

"And what do you think happened next?"

"I think that she si