In vain I attempted to fling myself between them.  In vain the waiters rushed to and fro, imploring “ces Messieurs” to interpose.  In vain a stout man pushed his way through the bystanders, exclaiming angrily:—­

“Desist, Messieurs!  Desist, in the name of the law!  I am the proprietor of this establishment—­I forbid this brawling—­I will have you both arrested!  Messieurs, do you hear?”

Suddenly the flush of rage faded out of Mueller’s face.  He gasped—­became livid.  Lepany, Droz, myself, and one or two others, flew at the stranger and dragged him forcibly back.

“Assassin!” I cried, “would you murder him?”

He flung us off, as a baited bull flings off a pack of curs.  For myself, though I received only a backhanded blow on the chest, I staggered as if I had been struck with a sledgehammer.

Mueller, half-fainting, dropped into a chair.

There was a tramp and clatter at the door—­a swaying and parting of the crowd.

“Here are the sergents de ville!” cried a trembling waiter.

“He attacked me first,” gasped Mueller.  “He has half strangled me.”

“Qu’est ce que ca me fait!” shouted the enraged proprietor.  “You are a couple of canaille!  You have made a scandal in my Cafe.  Sergents, arrest both these gentlemen!”

The police—­there were two of them, with their big cocked hats on their heads and their long sabres by their sides—­pushed through the circle of spectators.  The first laid his hand on Mueller’s shoulder; the second was about to lay his hand on mine, but I drew back.

“Which is the other?” said he, looking round.

“Sacredie!” stammered the proprietor, “he was here—­there—­not a moment ago!”

“Diable!” said the sergent de ville, stroking his moustache, and staring fiercely about him.  “Did no one see him go?”

There was a chorus of exclamations—­a rush to the inner salon—­to the door—­to the street.  But the stranger was nowhere in sight; and, which was still more incomprehensible, no one had seen him go!

“Mais, mon Dieu!” exclaimed the proprietor, mopping his head and face violently with his pocket-handkerchief, “was the man a ghost, that he should vanish into the air?”

“Parbleu! a ghost with muscles of iron,” said Mueller.  “Talk of the strength of a madman—­he has the strength of a whole lunatic asylum!”

“He gave me a most confounded blow in the ribs, anyhow!” said Lepany.

“And nearly broke my arm,” added Eugene Droz.

“And has given me a pain in my chest for a week,” said I, in chorus.

“If he wasn’t a ghost,” observed the fat student sententiously, “he must certainly be the devil.”

The sergents de ville grinned.

“Do we, then, arrest this gentleman?” asked the taller and bigger of the two, his hand still upon my friend’s shoulder.

But Mueller laughed and shook his head.