Chick carried him to a drug store with the aid of a policeman.

An ambulance was summoned; Nick was put into it.

But when the ambulance reached the hospital there was nobody inside it except the surgeon, who winked to the driver and went to his room.

Nick and Chick presently met again.

“Did you see the person who got out of that carriage?” asked Nick.

“I caught a glimpse of him,” Chick replied. “He was a tall man with a light-brown beard. I have no doubt he is the same man whom you saw last night.”

“Then we’ve gained a point. We have worked down to the man who is directing all these operations. Three times he has appeared. This settles it.”

“In other words,” said Chick, “we have seen Doc Helstone.”

“Exactly.”

“He is a slippery rascal.”