put the
first two fingers of each hand into his mouth and blow out a shrill,
ear-splitting whistle. "That'll fetch him! He'll be here before you can
say Jack Robinson!"

He wasn't, of course; but you couldn't have said it half a hundred times
before he was; or, at least, before Cleek, startled by a rustling of the
boughs, glanced round and saw a tall, fairish young man who had no more
the appearance of a soldier than a currant has of a gooseberry. He
looked more like a bank clerk than anything else that Cleek could think
of at the minute, and a none too prepossessing bank clerk at that, for
Nature had not been any too lavish of her gifts as regards personal
attractiveness, seeming to prefer to make up for her miserliness in the
bestowal of good looks by an absolute prodigality in the gifts of
ears--ears as big as an oyster-shell and so prominent that they seemed
even larger than they were, and that is saying a great deal.

Still, unprepossessing as the man was, there was a certain charm of
manner about him and a certain attractiveness in his voice Cleek
discovered when he was introduced to him and found himself being "sized
up," so to speak, by a pair of keen grey eyes.

"Now let us have the details of the case, if you please, Captain," said
Cleek, coming to the point of the interview with as little beating about
the bush as possible. "Mr. Narkom has given me a vague idea of the
nature of it, but I want something more than that, of course. I am told
that three persons in one family have been done to death in a most
mysterious manner, and without any clue to the assassin or his motive;
indeed that the hand which strikes strikes even in the presence of
others, yet remains unknown and invisible. Frankly, I never heard of but
one instance which at all resembles this or--No, Mr. Narkom, it is
nothing that ever came your way, no affair that has happened since you
and I first met, sir. It was a long time ago--eight or ten years, to be
exact--and a good many miles from England. The cases were somewhat
similar, judging from the scanty outline you have given me, and--What's
that? No, the criminal was never apprehended. He got away, and his
methods were never generally known. Even if they had been, they were not
those which any desperado might have emulated, any tyro practised. They
required a certain knowledge of anatomy, chemical action--even surgery.
I don't believe that ten people in the world knew about the thing at
that t