Mr. Hucks said it thoughtfully, but his mind was not working with his speech.  The coals, as he knew—­though he did not propose to tell the Doctor, at any rate just yet—­had been delivered by Sam Bossom.  Of complicity in any such plot as this Sam was by nature incapable.  On the other hand, Sam was just the fellow to help a couple of children out of mere kindness of heart.  Mr. Hucks decided to have a talk with Sam before committing himself.  He suspected, of course—­nay, was certain—­that Glasson had kept back something important.

Thus his meditations were running when the Doctor’s reply switched the current in a new direction.

“You have not heard the whole of it.  As it happens, the man in charge of the coal-boat was not, as I should judge, one of your regular employees—­certainly not an ordinary bargeman—­but a person whose speech betrayed him as comparatively well educated.”

“Eh?” Mr. Hucks sat upright and stared.

“I am not suggesting—­”

“No, damme—­you ’d better not!” breathed Mr. Hucks.

“Very possibly he had bribed your man with the price of a pot of beer.  At all events, there he was, and in charge of the boat.”

“You saw him?  Spoke to him?”

“To be accurate, he spoke to me—­down the coal-shaft, as I was examining it.  I judged him to be simulating drunkenness.  But his voice was a cultivated one—­I should recognise it anywhere; and Mrs. Huggins, who saw and spoke with him, describes him as a long-faced man, of gentlemanly bearing, with a furred collar.”

“Good Lord!  Mortimer!” ejaculated Mr. Hucks, but inwardly.

“I need hardly point out to you that a bargee in a furred collar—­”

“No, you needn’t.”  Mr. Hucks rose from his chair.  “See here, Glasson, you’ve come with a notion that I’m mixed up in this.  Well, as it happens, you’re wrong.  I don’t ask you to take my word—­I don’t care a d—­n whether you believe me or not—­only you’re wrong.  What’s more, I’ll give no promise to help—­not to-night, anyway.  But I’m goin’ to look into this, and to-morrow I’ll tell you if we play the hand together.  To-morrow at nine-thirty, if that suits?  If not, you can go and get the police to help.”

“Time may be precious,” hesitated Glasson.

“Mine is, anyway,” Mr. Hucks retorted.  “Let me see you out.  No, it’s no trouble.  I’m goin’ to look into this affair right away.”

He handed the Doctor his lantern, opened the door for him, and walked with him three parts of the way across the yard.  As they passed the caravan door his quick ear noted a strange sound within.  It resembled the muffled yap of a dog.  But Mr. and Mrs. Mortimer did not keep a dog.

He halted.  “There’s the gate.  Good night,” he said, and stood watching while Glasson passed out.  Then, swinging on his heel, he strode back to the caravan.

“Mortimer!” he challenged, mounting to the third step and knocking.