electric light upon the stained glass window that brought it back to me,
for on the night of the day when I first heard it in Paris a strong light
was falling upon the stained glass windows of the church opposite the house
in which I had apartments."

"Perhaps, then," I suggested, "the law of association may operate again if
you take the trouble to walk back and repass the church in the same manner
and the same state of mind, as nearly as you can resume them."

"By Jove," said the doctor, who likes experiments of this kind, "I'll try
it. Wait for me here."

I stood at the corner while the doctor briskly retraced his steps. His
firmly built, comfortable-looking form passed rapidly away. Within five
minutes he was back, a triumphant smile lighting his face.

"Success!" he said. "I have it, although whether from chance or as a result
of repeating my impression of light falling on a church window I can't say.
Certainly, after all these years, the tune is again mine. Listen."

As we proceeded up the street the doctor whistled a few measures composing
a rather peculiar melody, expressive, it seemed to me, of unrest. I never
forget a tune I have once heard, and this one was soon fixed in my memory.

"And the interesting circumstances under which you heard it?" I
interrogated. "Surely after the concern I've shown in the matter, you're
not going to deprive me of the story that goes with the tune?"

"There is no reason why I should. But I hope you will not circulate the
melody. It is the music that accompanies a tragedy."