che? What of him?"

"A great deal of him. But there are other men who are slight, other men
who have little dark moustaches, Colonel. That description would answer
for Captain Crawford here; and if he, too, were in town to-day----"

"I was in town!" blurted out the captain, a sudden tremor in his voice,
a sudden pallor showing through his tan. "But, good God, man! you--you
can't possibly insinuate----"

"No, I do not," interposed Cleek. "Set your mind at rest upon that
point, Captain; for the simple reason that the little dark man is a
little dark fiction; in other words, he does not and never did exist!"

"What's that?" fairly gasped Narkom. "Never existed? But, my dear Cleek,
you told me that the porter at London Bridge saw him and----"

"I told you what the porter told me; what the porter thought he saw, and
what we shall, no doubt, find out in time at least fifty other people
thought they saw, and what was, doubtless, the 'good joke' alluded to in
the forged note. The only man against whom we need direct our attention,
the only man who had any hand in this murder, is a big, burly,
strong-armed one like Colonel Murchison here."

"What's that?" roared out the colonel furiously. "By the Lord Harry, do
you dare to assert that I--I sir--killed the man?"

"No, I do not. And for the best of reasons. The assassin was shut up in
that compartment with Lord Stavornell from the moment he left London
Bridge; and I happen to know, Colonel, that although you were in town
to-day, you never put foot aboard the 5.28 from the moment it started to
the one in which it stopped. And at that final moment, Colonel," he
reached round, took something from his pocket, and then held it out on
the palm of his hand, "at that final moment, Colonel, you were passing
the barrier at the Crystal Palace Low Level with a lady, whose ticket
from London Bridge had never been clipped, and with this air-pistol,
which she had restored to you, in your coat pocket!"

"W-w-what crazy nonsense is this, sir? I never saw the blessed thing in
all my life."

"Oh, yes, Colonel. Loader, of Tottenham Court Road, repaired the valve
for you the day before yesterday, and I found it in your room just----
Quick! nab him, Petrie! Well played! After the king, the trump; after
the confederate, the assassin! And so----" He sprang suddenly, like a
jumping cat, and there was a click of steel, a shrill, despairing cry,
then the rustle of something falling. When Captain Cr