That evening Mr. Ormskirk continued the subject of his talk of the
afternoon.

"You looked surprised, Edgar, when I said that I told Sir Ralph I had made
some preparations for defence, and that some of the compounds in my
laboratory are as dangerous as the common people regard them, although
that danger has naught to do with any magical property. You must know that
many substances, while wholly innocent in themselves, are capable of
dealing wide destruction when they are mixed together; for example,
saltpetre, charcoal, and sulphur, which, as Friar Bacon discovered, make,
when mixed together, a powder whose explosive power is well-nigh beyond
belief, and which is now coming into use as a destructive agent in war.
Many other compounds can be produced of explosive nature, some indeed of
such powerful and sudden action that we dare not even make experiments
with them.

"Many other strange things have been discovered, some of which may seem
useless at present, but may, upon further experiments on their properties,
turn out of value to man. Such a substance I discovered two years ago. I
was experimenting upon bones, and endeavouring to ascertain whether a
powder might not be procured which, when mixed with other substances,
would produce unexpected results. After calcining the bones, I treated the
white ash with various acids and alkaloids, and with fire and water,
returning again and again to the trials when I had time. While conducting
these experiments, I found that there was certainly some substance present
with whose nature I was altogether unacquainted.

"One evening, going into the laboratory after dark, I observed with
astonishment what looked like a lambent flame upon the table. In my alarm