The first-prompted suspicion that Mordecai might be liable to hallucinations of thought--might have become a monomaniac on some subject which had given too severe a strain to his diseased organism--gave way to a more submissive expectancy. 
His first suspicion that Mordecai might be liable to hallucinations, obsessed by some subject which had over-strained his diseased body, gave way to a submissive expectancy. 