When Isaac Mole had time to reflect coolly upon what had occurred, doubts arose in his mind.
In spite of the seemingly inexplicable nature of the phenomena which he had witnessed, he felt that Harkaway, father or son, must know something of it.
Dick Harvey, he was morally sure, was in it.
If any thing fell, Harkaway would start up, on which Harvey or young Jack would immediately inquire anxiously if he were startled, solely for the purpose of leading up to Mole's words at the wizard's house.
"Startled—nervous! Never; iron nerves, sir—adamant!"
Upon these occasions, Mr. Mole would glide away from Harkaway's room without a word, leaving his tormentors to have their grin out all to themselves.
All they could do they could not make him drop a word of allusion to the events just narrated.
On that topic he was utterly dumb. Day and night the worthy Isaac Mole brooded over one solitary topic.
Revenge.
"I'll teach 'em," he said; "I'll let them know what it is to play practical jokes with a man like me."