that held by the police could be sustained. But so far he did
not see his way to an alternative theory. He sought vainly for a
foundation on which to build his clues and discoveries; for some
overlooked trifle which would help him to read aright the true order and
significance of the jumbled assortment of events in this strange case.

In the first place, was Ronald's explanation, about losing his way and
wandering to the inn by chance, the true one? The police accepted it
without question, but was it likely that a man who was in the habit of
taking long walks about the coast would lose his way easily? As against
that doubt, there were the statements of the innkeeper and the deaf
waiter that they had never seen Ronald before. If Ronald were not
guilty, why had he departed so hurriedly from the inn that morning? And
if he were not the murderer what was the explanation of the damning
evidence of the footprints leading to the pit in which the body of the
murdered man had been flung? If the discovery of the two kinds of
candle-grease in Mr. Glenthorpe's bedroom indicated that two persons
were in the room on the night of the murder, who were those two persons,
and what did they both go there for?

He reflected that his only tangible reason, so far, for not accepting
the police theory was based on the belief that two people had been in
the murdered man's room, and that belief rested on the discovery of a
spot of candle-grease which in itself was merely presumptive, but not
conclusive evidence. It was necessary to establish beyond doubt the
supposition that two people had been in the room before he could presume
to draw inferences from it. And, if he succeeded in establishing that
supposition, might not Ronald have been one of the two persons, and the
actual murderer? What was the significance of the broken incandescent
burner, the turned-on gas, and the faint mark under the window?

These questions revolved in Colwyn's head in a circle, always bringing
him back to his starting point that the solution of the case did not lie
on the surface, and that the police theory could not be made to fit in
with his own discoveries. The latter were in themselves internal
evidence that the whole truth had not yet been brought to light.

Gradually the line of the circle grew nebulous, and Colwyn was fast
falling asleep through sheer weariness, when a slight sharp sound, like
that made by turning a key in a lock, brought him back to wide-ey