I could see that there were other questions which Holmes would have wished to put, but the nobleman’s abrupt manner showed that the interview was at an end. It was evident that to his intensely aristocratic nature this discussion of his intimate family affairs with a stranger was most abhorrent, and that he feared lest every fresh question would throw a fiercer light into the discreetly shadowed corners of his ducal history.

When the nobleman and his secretary had left, my friend flung himself at once with characteristic eagerness into the investigation.

The boy’s chamber was carefully examined, and yielded nothing save the absolute conviction that it was only through the window that he could have escaped. The German master’s room and effects gave no further clue. In his case a trailer of ivy had given way under his weight, and we saw by the light of a lantern the mark on the lawn where his heels had come down. That one dint in the short, green grass was the only material witness left of this inexplicable nocturnal flight.