for inspection.

"Are those good tests for genuineness?" we asked the professor, aside.

"As to that," he replied regretfully, "I do not know. I know of coral
only that is the hard calcareous skeleton of the marine coelenterate
polyps; and that this red coral iss called of a sclerobasic group; and
other facts of the kind; but I do not know if it iss supposed to resist
impact and heat. Possibly," he ended shrewdly, "it is the common
imitation which does _not_ resist impact and heat. At any rate they are
pretty. How much?" he demanded of the vendor, a bright-eyed Egyptian
waiting patiently until our conference should cease.

"Twenty shillings," he replied promptly.

The professor shook with one of his cavernous chuckles.

"Too much," he observed, and handed the necklace back through the
window.

The Egyptian would by no means receive it.

"Keep! keep!" he implored, thrusting the mass of red upon the professor
with both hands. "How much you give?"

"One shilling," announced the professor firmly.

The coral necklace lay on the edge of the table throughout most of our
leisurely meal. The vendor argued, pleaded, gave it up, disappeared in
the crowd, returned dramatically after an interval. The professor ate