? People have been murdered with the
mildest domestic comforts; certainly with tea-kettles, probably with
tea-cosies. On the other hand, if you showed an Ancient Briton a
revolver, I doubt if he would know it was a weapon--until it was fired
into him, of course. Perhaps somebody introduced a firearm so new that
it didn't even look like a firearm. Perhaps it looked like a thimble or
something. Was the bullet at all peculiar?"

"Not that I ever heard of," answered Flambeau; "but my information is
fragmentary, and only comes from my old friend Grimm. He was a very able
detective in the German service, and he tried to arrest me; I arrested
him instead, and we had many interesting chats. He was in charge here
of the inquiry about Prince Otto, but I forgot to ask him anything about
the bullet. According to Grimm, what happened was this." He paused a
moment to drain the greater part of his dark lager at a draught, and
then resumed:

"On the evening in question, it seems, the Prince was expected to appear
in one of the outer rooms, because he had to receive certain visitors
whom he really wished to meet. They were geological experts sent to
investigate the old question of the alleged supply of gold from the
rocks round here, upon which (as it was said) the small city-state
had so long maintained its credit and been able to negotiate with
its neighbours even under the ceaseless bombardment of bigger armies.
Hitherto it had never been found by the most exacting inquiry which
could--"

"Which could be quite certain of discovering a toy pistol," said Father
Brown with a smile. "But what about the brother who ratted? Hadn't he
anything to tell the Prince?"

"He always asseverated that he did not know," replied Flambeau; "that
this was the one secret his brothers had not told him. It is only right
to say that it received some support from fragmentary words--spoken by
the great Ludwig in the hour of death, when he looked at Heinrich but
pointed at Paul, and said, 'You have not told him...' and was soon
afterwards incapable of speech. Anyhow, the deputation of distinguished
geologists and mineralogists from Paris and Berlin were there in the
most magnificent and appropriate dress, for there are no men who like
wearing their decorations so much as the men of science--as anybody
knows who has ever been to a soiree of the Royal Society. It was a
brilliant gathering, but very late, and gradually the Chamberlain--you
saw his portrait,