half an opportunity he would have upset the glass, but I
was on the watch for that. My right hand was in my pocket; the same in
which I had placed the revolver, and from the expression upon his face I
gathered that he was aware of the fact. At last, seeing that there was
nothing for it but to do as I desired, he lifted the glass and tossed
off the contents. I assured myself that he had left no heel-tap, and
then bade him be seated, returning myself to the game of cards which the
old man's entry had interrupted. The strength of the drug must have been
considerable, for we had not played more than a dozen hands before his
head had fallen forward on the table, and he was fast asleep. I
convinced myself that he was not shamming, and then turned to the old
man.

"'You see, my venerable friend,' I said, 'what your fate would have been
had you drunk what was in that glass. For the future were I in your
place, I should bestow my patronage elsewhere. This inn is not safe for
you. And now let me escort you to your dwelling. Our friends here are
none too amiably disposed towards you, and it is just possible they
might take their revenge as soon as my back was turned.' With that we
left the inn together and tramped along the track, till we reached the
miserable hovel in which he lived. During our walk the old fellow had
scarcely spoken. Now he became somewhat more communicative.

"'I am obliged to you, Senor, for what you have done for me,' he began.
'They hate me over there because they think I know more about diamonds
than they do.' He was silent again for a few moments. 'And it's quite
true,' he added solemnly to himself.

"At the time I regarded this as only another proof of the old boy's
idiocy. I had often seen him polishing his pebbles, and, like every one
else, had come to the conclusion that he believed them to be diamonds.
Now, however, I have the very best of reasons for knowing that it was
only another proof of his cleverness. It suited him to pose as a softy,
and the pebbles were only a means he had adopted for putting us off the
scent.

"'When you come to think of it, it was rather a good thing for you that
I visited the hospederia to-night,' I said, when I had seated myself on
a log that did duty for a chair, and had lit a cigar. For you see I
wanted him to understand plainly that I had rendered him a service, and
also that I expected him to be grateful for the same. 'If I hadn't been
at hand they'd have played