rosi, and
is certainly a most dangerous poison in the hands of anyone with
criminal intent, because no post-mortem examination known to the
medical profession to-day would be able to detect whether the victim
had been murdered or died of natural causes."

"It astounds me!" I gasped.

"No doubt. But to me, of course, it is a most interesting piece of
research," and the professor went on: "I have never met this substance
before, though I had heard whispers of it. Professor Orosi, who lived
in Cologne a few years ago and is now dead, produced this poison quite
accidentally, and among his intimate friends disclosed its existence,
though he had no idea how to test for it with certainty. For five
years all toxicologists made constant tests until apparently quite by
accident Professor Sonnenschein, of Hanover, discovered the reagent
which would reveal the actual glucosid, and determine its identity. It
gives a yellowish-white precipitate," he added, holding up for my
inspection a small test-tube containing a liquid of the colour he had
indicated.

"Marvellous!" I exclaimed. "I had no idea that medical science could
carry inquiries so far. I know that in criminal cases in London our
pathologists, with their mirror-tests for arsenic, fix the guilt upon
poisoners in a manner most amazing. But I have never heard of this
secret and most subtle poison which was placed beside my bed, the
intention being for me to tread upon the impregnated pin."

"And if you had done so you would have been taken with a sudden fatal
seizure, the cause of which would never have been detected."

"You mean I should have died of poison?"

"You certainly would. No medical aid would have been of any avail, for
orosin is the most deadly substance which has ever been discovered. It
is indeed good for humanity that it is known to only a few
toxicologists, but that in itself reveals the fact, monsieur, that an
exceedingly clever and secret attack has been made upon your life. A
single puncture of the skin with one or other of those pins which were
placed so conveniently at your bedside when you sprang out to meet the
intruder, and you would by this time have been buried as one whose
death had been due to natural causes!"

I held my breath. This declaration by one of the greatest professors
of toxicology in Europe staggered me. A dastardly attempt had been
made upon me by one of the most notorious of modern criminals!

Why? No attempt at assassination