r like a diamond. But, if so, it is a Behemoth of diamonds. Where
did you get it?"

"I tell you I made it," he said. "Give it back to me."

He replaced it hastily and buttoned his jacket. "I will sell it you
for one hundred pounds," he suddenly whispered eagerly. With that my
suspicions returned. The thing might, after all, be merely a lump
of that almost equally hard substance, corundum, with an accidental
resemblance in shape to the diamond. Or if it was a diamond, how came
he by it, and why should he offer it at a hundred pounds?

We looked into one another's eyes. He seemed eager, but honestly
eager. At that moment I believed it was a diamond he was trying to
sell. Yet I am a poor man, a hundred pounds would leave a visible gap
in my fortunes and no sane man would buy a diamond by gaslight from a
ragged tramp on his personal warranty only. Still, a diamond that size
conjured up a vision of many thousands of pounds. Then, thought I,
such a stone could scarcely exist without being mentioned in every
book on gems, and again I called to mind the stories of contraband and
light-fingered Kaffirs at the Cape. I put the question of purchase on
one side.

"How did you get it?" said I.

"I made it."

I had heard something of Moissan, but I knew his artificial diamonds
were very small. I shook my head.

"You seem to know something of this kind of thing. I will tell you
a little about myself. Perhaps then you may think better of the
purchase." He turned round with his back to the river, and put his
hands in his pockets. He sighed. "I know you will not believe me."

"Diamonds," he began--and as he spoke his voice lost its faint flavour
of the tramp and assumed something of the easy tone of an educated
man--"are to be made by throwing carbon out of combination in a
suitable flux and under a suitable pressure; the carbon crystallises
out, not as black-lead or charcoal-powder, but as small diamonds. So
much has been known to chemists for years, but no one yet has hit upon
exactly the right flux in which to melt up the carbon, or exactly the
right pressure for the best results. Consequently the diamonds made by
chemists are small and dark, and worthless as jewels. Now I, you know,
have given up my life to this problem--given my life to it.

"I began to work at the conditions of diamond making when I was
seventeen, and now I am thirty-two. It seemed to me that it might take
all the thought and energies of a man for ten yea