and that he may have designs upon the
_Malplaquet_?" said I.

"I don't propose to tell you what I think," replied Dawson stiffly.

"Still," I persisted, passing over the snub, "you have a theory?"

"No, thanks," said Dawson contemptuously. "I have no use for theories.
When they are wrong they mislead you, and when they are right they are
no help. I believe in facts--facts brought out by constant vigilance.
Unsleeping watchfulness and universal suspicion, those are the
principles I work on. The theory business makes pretty story books,
but the Force does not waste good time over them."

"What are you going to do?"

"This is Thursday afternoon. I am going to join the _Malplaquet_
presently, and I'm not going to sleep till she is safely down the
river. I'm going to be my own watchman this time."

"How? In what capacity?"

Dawson gave a shrug of impatience, for his nerves were on edge. For a
moment he hesitated, and then, recollecting the high post to which I
had tacitly been appointed in his household, he replied:

"I am going as one of the Marine sentries."

"It's no use, Dawson," protested I emphatically. "You are a wonder at
disguise, and will look, I do not doubt, the very spit of a Marine.
But you can't pass among the men for half an hour without discovery.
They are a class apart, they talk their own language, cherish their
own secret traditions, live in a world to which no stranger ever
penetrates. You could pass as a naval officer more easily than you
could as a Pongo. It is sheer madness, Dawson."

He gave a short laugh. "Much you know about it. I have served in the
Red Corps myself. I was a recruit at Deal, passed two years at
Plymouth, and served afloat for three years. I was then drafted into
the Naval Police. Afterwards I was recommended for detective work in
the dockyards, and at the end of my Marine service joined the Yard. My
good man, I was a sergeant before I left the Corps."

"I give up, Dawson," said I. "Nothing about you will ever surprise me
again. Not even if you claim to have been a Cabinet Minister."

A queer smile stole over his face. "No, I have not been a minister,
but I have attended a meeting of the Cabinet."

Cary interposed at this point. "Yours is a fine idea, Mr. Dawson. As a
Marine sentry you can get yourself posted by the Major wherever you
please, and the Guard will not talk even though they may wonder that
any man should want to do twenty-four hours of duty per day. The