the firework
display. A halfhearted attempt was made at dancing, but the howling of
the wind, and the omnipresent dust, perpetually reminded the
pleasure-seekers that _Khamsin_ raged without--raged with a violence
unparalleled in the experience of the oldest residents. This was a
full-fledged sand-storm, a terror of the Sahara descended upon Cairo.

But there were few departures, although many of the visitors who had
long distances to go, especially those from Mena House, discussed the
advisability of leaving before this unique storm should have grown
even worse. The general tendency, though, was markedly gregarious;
safety seemed to be with the crowd, amid the gaiety, where music and
laughter were, rather than in the sand-swept streets.

"Guess we've outstayed our welcome!" confided an American lady to
Sime. "Egypt wants to drive us all home now."

"Possibly," he replied with a smile. "The season has run very late,
this year, and so this sort of thing is more or less to be expected."

The orchestra struck up a lively one-step, and a few of the more
enthusiastic dancers accepted the invitation, but the bulk of the
company thronged around the edge of the floor, acting as spectators.

Cairn and Sime wedged a way through the heterogeneous crowd to the
American Bar.

"I prescribe a 'tango,'" said Sime.

"A 'tango' is--?"

"A 'tango,'" explained Sime, "is a new kind of cocktail sacred to this
buffet. Try it. It will either kill you or cure you."

Cairn smiled rather wanly.

"I must confess that I need bucking up a bit," he said: "that
confounded sand seems to have got me by the throat."

Sime briskly gave his orders to the bar attendant.

"You know," pursued Cairn, "I cannot get out of my head the idea that
there was someone wearing a crocodile mask in the garden a while ago."

"Look here," growled Sime, studying the operations of the cocktail
manufacturer, "suppose there were--what about it?"

"Well, it's odd that nobody else saw him."

"I suppose it hasn't occurred to you that the fellow might have
removed his mask?"

Cairn shook his head slowly.

"I don't think so," he declared; "I haven't seen him anywhere in the
hotel."

"Seen him?" Sime turned his dull gaze upon the speaker. "How should
you know him?"

Cairn raised his hand to his forehead in an oddly helpless way.

"No, of course not--it's very extraordinary."

They took their seats at a small table, and in mutual silence loaded
and lighte