Allerdyke suddenly bent his head towards the table.

“Careful!” he said.  “Gad!—­I know one of ’em, anyhow.  Van Koon, as I live!”

CHAPTER XXXII

THE CHILVERTON ANTI-CLIMAX

The chief allowed himself to take a quick searching glance at the two men he had indicated.  He had already heard of Van Koon and of his sudden disappearance from the hotel after the chance encounter with Chilverton, and he now regarded him with professional interest.

“The tall man, you mean?” he asked.

“Just so,” answered Allerdyke.  “The other man I don’t know.  But that’s Van Koon.  What’s he here for, now?  Is he in this, after all?”

The chief made no reply.  He was furtively watching the two men, who had dropped into chairs at a vacant table beneath the shade of the trees and were talking to a waitress.  Having taken a good look at Van Koon, he turned his attention to Van Koon’s companion, a little, dapper man, smartly dressed in bright blue serge, and finished off with great care in all his appointments.  He seemed to be approaching middle age; there were faint traces of grey in his pointed beard and upward-twisted moustaches; he carried his years, however, in very jaunty fashion, and his white Homburg hat, ornamented with a blue ribbon, was set at a rakish angle on the side of his close-cropped head.  In his right eye he wore a gold-rimmed monocle; just then he was bringing it to bear an the waitress who stood between himself and his companion.

“You don’t know the other man, either of you?” asked the chief suddenly.

Allerdyke shook his head, but Appleyard nodded.

“I know that chap by sight,” he said.  “I’ve seen him in the City—­about Threadneedle Street—­two or three times of late.  He’s always very smartly dressed—­I took him for a foreigner of some sort.”

The chief turned to his coffee.

“Well—­never mind him,” he said.  “Pay no attention—­so long as that man is Van Koon, I’ll watch him quietly.  But you may be sure he has come here on the same business that has brought us here.  I—­”

Allerdyke, whose sharp eyes were perpetually moving round the crowded enclosure and the little groups which mingled outside it, suddenly nudged the chief’s elbow.

“Miss Slade!” he whispered.  “And—­Rayner!”

Appleyard had caught sight of his two fellow inmates of the Pompadour at the very moment in which Allerdyke espied them.  He slightly turned away and bent his head; Allerdyke followed his example.

“You can’t mistake them,” he said to the chief.  “I’ve described the man to you—­a hunchback.  They’re crossing through the crowd towards the tea-house door.”

“And they’ve gone in there,” replied the chief in another minute.  “Um!—­this is getting more mysterious than ever.  I wish I could get a word with some of our men who really know something!  It seems to me—­”