sort of footprints when we go into the
laboratory--damp ones, you know, from the moisture of the earth; and
to make sure, in case we do find 'em let's take the length of the
things and see. Got a tape measure with you? No? Oh, well, lend
me your handcuffs, if you've got a pair with you, and we can manage
a measurement with those. Thanks very much. Now, then, let's see.
One, two, three, by Jupiter--three fingers longer than these things,
chain and all. That'll do. Now, then, let's go in and see about the
others. Lead the way, Miss Renfrew, if you will."

She would, and did. Leading the way back to the covered passage,
she opened a door in the side of it--a door designed to let the
inventor out into the grounds without going through the house, if he
so desired--and conducted them to the laboratory, leaving Constable
Gorham to continue his dreary sentry duty outside.

At any time the interior of that huge, stone-walled, steel-lined
tube must have been unlovely and depressing to all but the man who
laboured in it. But to-night, with that man sitting dead in it,
with his face to the open window, a lamp beside him, and stiff hands
resting on the pages of a book that lay open on the desk's flat top,
it was doubly so; for, added to its other unpleasant qualities,
there was now a disagreeable odour and a curious, eye-smarting,
throat-roughening heaviness in the atmosphere which was like to
nothing so much as the fumes thrown off by burnt chemicals.

Cleek gave one or two sniffs at the air as he entered, glanced at Mr.
Narkom, then walked straightway to the desk and looked into the dead
man's face. Under the marks of the scratches and cuts upon it--marks
which would seem to carry out the idea of an animal's attack--the
features were distorted and discoloured, and the hair of beard and
moustache was curiously crinkled and discoloured.

Cleek stopped dead short as he saw that face, and his swaggering,
flippant, cocksure air of a minute before dropped from him like a
discarded mantle.

"Hullo! this doesn't look quite so promising for the animal theory
as it did!" he flung out sharply. "This man has been shot--shot
with a shell filled with his own soundless and annihilating devil's
invention, lithamite--and bomb throwing is _not_ a trick of beasts of
a lower order than the animal tribe! Look here, Mr. Narkom--see! The
lock of the desk has been broken. Shut the door there, Nippers.
Let nobody leave the room. There has been murd