d see that back of the lounge.

I said to myself, "Is this a dream or the effect of the powder I have
taken?" and I pinched my leg, and rubbed my eyes, but although I seemed
to be perfectly wide awake, the shape did not disappear.

"What did you say?" I asked.

"I remarked that the subject of high explosives was decidedly
interesting," answered the shape. "I was a chemist when alive, but it
makes me sad to think how very little I really knew. Chemistry, as well
as other branches of science, has made great strides during the past
generation, since my day, but even now they really know very little."

"But," I answered, "it seems to me the high explosives which we now have
are sufficiently powerful if we knew how to use them with safety."

"That's it," answered the shape. "Now, I have a couple of hours to
spare, and, if it would interest you, and you care to come over to my
laboratory, I will be happy to give you one or two points which may
prove of value to you--I say to my laboratory, but it really is not
mine; I use any laboratory that is handiest, and I know most of the good
ones in the city. You see, I do not need to have a key to enter a room;
that is one of the great advantages we have, as you will discover one of
these days. Just now I can get you in very well because the owner of the
laboratory to which we will go is out of town. I will go in first and
unlock the door for you."

I told him that I should be most happy to accept his invitation; it
seemed the most natural thing in the world to be conversing with a ghost
and to have him invite me to go to somebody's laboratory and use up his
chemicals. It never occurred to me that it might not be considered quite
good form. We went out of my rooms and downstairs, the shadow floating
alongside of me in the most friendly manner possible. I could see by the
position of his body that he had hold of my arm, but his fingers did not
show on my coat-sleeve.

We went up town for perhaps half a mile, and entered a large brick
building in which I noted were various studios. It was dark, but going
up three flights of stairs my guide opened a door and ushered me into a
large and extensively furnished laboratory, evidently belonging to some
scientific man of means and experience. The ghost turned the button of
the electric light, and then motioned me to a seat.

"My time," he said, "is somewhat limited, because I have an appointment
with a lady at twelve, but I will show yo